Weapons of Mass Destruction (WMD)

STRATEGIC NUCLEAR WEAPONS AND DETERRENCE

29 November 2005

Edward A. Corcoran

This paper examines the utility of strategic nuclear weapons. These weapons, a legacy of the Cold War, were developed to deter Soviet actions which would threaten vital interests or the survival of the United States. Such strategic deterrence seeks to convince adversaries that the benefits of hostile actions would be far outweighed by the consequences.[1] More recently, as the Soviet threat has all but disappeared, emerging nuclear threats from proliferation and terrorism reinforce the need for deterrence. Nevertheless, the usefulness of nuclear weapons in general and strategic nuclear weapons in particular has drastically declined.

Although there has been extensive military planning for the use of nuclear weapons in a deterrent role, there has been relatively little public discussion, particularly about the present role of strategic nuclear weapons.[2] The current Doctrine for Joint Nuclear Operations is publicly available in draft form. It specifies 1700 - 2200 as the necessary number of "operationally deployed strategic nuclear warheads" to meet current requirements[3], with additional weapons kept in a non-deployed status. But it provides only very general guidance on how these weapons would be used. This doctrine is based on a February 2004 report of the Defense Science Board on Future Strategic Strike Forces[4]. This report also addressed the issue in very general terms. It envisioned a shift from a reliance on nuclear weapons and even recommended modifying some intercontinental and submarine-launched strategic missiles to carry non-nuclear warheads. The report focused on capabilities and called for nuclear weapons that produced much lower collateral damage[5]. It addressed notional contingencies, but did not look at specific adversaries or situations.

The exact size and composition of the US strategic nuclear forces are highly classified, but unclassified estimates outline their magnitude. Strategic forces in one estimate include some 529 Intercontinental Ballistic Missiles (ICBM), 360 Submarine Launched Ballistic Missiles (SLBM) and 77 strategic bombers. Most of these strategic delivery vehicles carry from 3 to 20 warheads with yields ranging from 100 to 500 kilotons.[6]

During the Cold War, nuclear deterrence was a core element of US national security strategy. This evolved out of the security situation in Europe. In the immediate post-war situation, overwhelming Soviet conventional forces threatened to dominate Western Europe. These conventional forces were initially countered by a US nuclear capability. But once the Soviets acquired their own nuclear capability, stepwise efforts to achieve nuclear superiority led to the dead end of Mutually Assured Destruction.

At this stage, each side had nuclear stockpiles numbering in the tens of thousands. Large complexes for the development, production and testing of nuclear weapons allowed each side to hold the other hostage. Diversified force structures insured that preemptive strikes could not disarm the opponent who would then mount an annihilatory response. The situation was marginally stable - each side balanced the other, but the balance was in constant danger of disruption by false warnings or misunderstandings. The Cuban Missile Crisis forced a sober recognition of some of these dangers; thorough analysis many years later showed that nuclear war was much closer than either side had recognized at the time. This crisis spurred arms control efforts which added stability to the situation. However, deterrence theory remained both an underpinning of US foreign policy and a rationale for the continued research, development, and testing of nuclear weapons.

The collapse of the Soviet Union also collapsed the Soviet threat to Western Europe. At some stages in the Cold War it might have been possible for the Soviets to envision a first strike on the United States. But the new security situation in Europe totally eliminated whatever warped rationality could have justified this. Both sides recognized these changes and have significantly reduced their strategic nuclear arsenals.

Now the US-Russian relationship is an ambivalent one, with cordial relations overlying some fundamental disagreements. Against this background, sizable US and Russian strategic nuclear forces remain frozen in adversarial postures. At the same time, the rise of other nuclear threats is forcing the nation to re-evaluate its strategic posture.

Any reassessment of nuclear needs and postures must start with a sober assessment of the threats facing the nation and the utility of nuclear forces in meeting them.

NUCLEAR THREATS

The United States now faces a variety of nuclear threats from both state and non-state actors. Each of these has its own complex set of unique and enigmatic circumstances. Libya has recently disbanded a nuclear weapons program. Iraq's program has been forcibly destroyed. But what might happen in the decades ahead remains unknowable.

Lesser Challenges

These lesser challenges put the United States (including overseas forces and bases) and its allies at risk of nuclear attack. But these challenges do not pose a risk of catastrophic attack across the entire nation. Detailed analyses of any of these threats is far beyond the scope of this paper. However, available materials provide overviews of the magnitude of the challenges.

NORTH KOREA

North Korea probably represents one of the most significant nuclear threats facing the nation. It is implacably hostile to the United States and unpredictable in its responses. For more than 60 years it has posed an invasion threat to South Korea, though the military balance has been increasingly tilting against its favor. North Korea now claims to have nuclear weapons, and Western analysts agree that it has had a capability to have produced them.[7]

For years North Korea's overwhelming conventional superiority on the peninsula was partly countered by US nuclear capabilities, much as the Soviet threat to West Europe had been countered by US nuclear weapons years earlier. But as South Korean military capabilities grew, the balance shifted so significantly that by the early 1990's, the United States had withdrawn all theater nuclear weapons from South Korea.

The core significance of North Korean nuclear weapons is that they make a US use of nuclear weapons unattractive in any military confrontation. A North Korean invasion would certainly require a strong US response. With so many US forces tied down in the Middle East, nuclear weapons might even be considered. The United States might also be tempted to use nuclear weapons to preempt a North Korean attack. Perhaps more disturbing is the North Korean nuclear program. Not only has North Korea withdrawn from the Nuclear Non-Proliferation Treaty and claimed to have actually developed its own nuclear weapons, but it appears to have been a major player in a worldwide black market in nuclear materials, information, and potential delivery vehicles. It has also been very intransigent during on-going discussions regarding its nuclear programs, insisting on a right to have its own nuclear energy reactors. More recently, tentative agreements have been reached, thanks largely to Chinese involvement. These have resulted in significant economic benefits to North Korea while difficult negotiations continue.[8]

The US Defense Counterproliferation Initiative and a later National Strategy to Combat Weapons of Mass Destruction include programs to tailor US weapons to destroy hostile weapons of mass destruction. Such counterproliferation actions could potentially include military strikes on nuclear and underground facilities as well as command and control installations.[9]

But targeting North Korea would be a daunting task. A detailed analysis of options is obviously far beyond the scope of this paper. Nevertheless, even an initial overview shows that military options are very restricted and the usefulness of high-yield strategic nuclear weapons is very limited. The situation is so difficult because of a number of major considerations, including:

- Nuclear Weapons. As noted above, North Korea claims to have such weapons and this greatly complicates any military action by the United States.

- Weak intelligence. Donald Gregg, a C.I.A. station chief in Seoul during the cold war who returned there as the American ambassador, has called North Korea "the longest-running intelligence failure." As a result, our knowledge of details of its military and political infrastructure are very limited. This significantly increases targeting uncertainties and hence requires much larger strikes to insure results.[10]

- Hardened facilities. Arthur Brown, who spent more than 20 years studying North Korea at the Central Intelligence Agency, has characterized the North Koreans as "mole people," commenting that, "there are hundreds, thousands of holes in the ground, and we don't know what's in them."[11] Individual military targets are routinely hardened -- strike aircraft, for example, are often placed in reinforced bunkers or tunnels.

- Damage recovery. Any post-war costs of reconstruction and decontamination, not to mention treatment of mass casualties, would fall to the South Koreans. As the experience of East Germany has shown, integrating economically backward North Korea into a prosperous South Korea would pose enough challenges without adding widespread devastation.

- Fallout. North Korea is a small country, surrounded by China, Russia, Japan, and South Korea. Fallout from any nuclear strikes would contaminate at least one if not more of these critical countries. Obviously, the fallout pattern would depend on the number and types of weapons used, as well as strike options, weather conditions, and other imponderables, so a definitive prior assessment is not possible. One computer simulation of a single higher-yield nuclear strike on a hardened North Korean target showed lethal fallout reaching Seoul and significant levels reaching into Japan.[12] Another simulation showed the fallout pattern reaching into the Sea of Japan, but also estimated that even a small nuclear weapon (5 KT) and favorable weather conditions would still result in 5000 prompt casualties.[13] Certainly, fallout severely constrains any US nuclear options, especially the use of higher-yield nuclear weapons.

- Seoul. South Korea in general and Seoul in particular is hostage to North Korean actions. The edge of Seoul is only some 25 miles from the Demilitarized Zone (DMZ) - within range of tactical missiles. Even without considering potential weapons of mass destruction (WMD), it would be very difficult to insure that North Korea could not inflict serious damage and high casualties on South Korea.

- Beleaguered leadership. Although they have faced little cohesive internal opposition, the North Korean leadership remains vulnerable; the experiences of numerous other Communist dictatorships have shown that popular pressures cannot be indefinitely contained. The North Korean leadership appears to put survival as a top priority. If this survival is directly attacked, the leadership has little incentive to negotiate and could well initiate as much destruction as it remained capable of.

- Allied objections. Because of these and other considerations, South Korea bends over backwards to avoid provocations to North Korea. It recently endorsed a North Korean right to develop nuclear energy, even when the United states was adamantly opposed to such a development, and has offered to supply large amounts of electricity if North Korea halts and nuclear weapons work.[14] South Korea is adamantly opposed to any use of nuclear weapons -- doubtless one of the reasons that President Bush ordered the removal of all such weapons from South Korea in 1991. Additionally, any strikes with long-range strategic weapons might well require overflights of Japan or Russia, neither of which would be likely to provide permission. Japan also remains adamantly opposed to any use of nuclear weapons.

- Threat Misperceptions. Distant launches targeted at North Korea could also be mistakenly identified by Russia or China as incoming strikes and initiate some sort of counter-actions against the United States.

Against this background, a first overview of potential targeting will consider several engagement scenarios and major target sets.

Engagement scenarios include:[15]

- Retaliation. In response to a North Korean strike on the United States, US force abroad, or US allies and their forces, the United States may face a situation where retaliatory action is required. Fortunately, North Korea has at most a very limited capability for a direct attack on the United States, perhaps using a ship to launch a medium-range missile or sneak a weapon into a US port. But it does have a significant capability to strike US forces abroad, particularly in Japan and South Korea, and it could also strike either or both of these US allies.[16] The North Korean government has its own unique priorities, but it is hard to construct credible scenarios which would lead it to carry out such strikes except in a situation of utter desperation or collapse. In such a situation, deterrence could play at most a minor role. A situation calling for a major military response could include targeting of cities, infrastructure, or command and control elements.

- WMD neutralization. Threats of North Korean use of WMD probably makes neutralization of these weapons a necessary component of any military scenario. Preemptive neutralization could also be considered in a crisis situation. This would require elimination of delivery systems, military stocks, and production facilities.

- Leadership incapacitation. This would certainly be an immediate objective in case of any military response and is also an independent preemptive possibility in a crisis situation. It would require rapid elimination of command and control facilities with a high degree of assurance so that retaliatory strikes would be unlikely.

- Military neutralization. This would require elimination of key military facilities and infrastructure.

- Comprehensive engagement. This would essentially be a combination of all of the above. It would be a major war situation in response to a North Korean attack southward or some major North Korean strikes.

According to the joint doctrine, nuclear targeting seeks to hold at risk those things which an adversary values highly. Target sets for the scenarios above could include the following:

- Major cities. Pyongyang, with a population of over two million as well as six other cities with populations over 300,000 are obviously of high value for the North Korean leadership. They are also soft targets which could be severely damaged by conventional attacks and easily destroyed by air bursts of relatively low-yield nuclear weapons. However, a retaliatory strike on Pyongyang would accomplish little. Whatever the North Korean leadership might have done, killing tens of thousands of wretched North Korean citizens after the fact would provide little recompense. In World War II, the United States atom bombed Hiroshima and Nagasaki, and fire bombed Tokyo and Dresden. The morality of those strikes is still debated and bitterness at the United States still remains. In the case of North Korea, the loss of Pyongyang would have minimal immediate impact on North Korea's war fighting ability and would ultimately face South Korea with a staggering reconstruction requirement. And it would certainly undermine US relations with other nations, particularly in Asia. Along these lines, the Defense Science Board report stressed the need to avoid disproportionate damage to a country's population.[17] So strikes on major cities are both unlikely and unattractive.

- Infrastructure. The experience of the systematic NATO destruction of Serbian infrastructure shows that this is a major task. This NATO effort was intentionally drawn out; a concentrated conventional attack on North Korean infrastructure (ports, power stations, transportation nodes, industry, etc.) would clearly require a large number of attack assets. While elimination of some targets (e. g., transportation or communications nodes) would have a short-term impact on North Korean military operations, effects of other strikes would be longer term. Infrastructure targets are generally soft targets, so low-yield nuclear weapons would certainly be adequate. The number of potential targets is unclear but would include major bridges, rail yards, power generation and transmission facilities, telecommunications centers, industrial plants, and fuel depots. Certainly there are at least 50 targets whose destruction would have a prompt impact on military operations.

- Command and control. Compared to cities and infrastructure, these are very different and very difficult targets. They include the people who would be responsible for any North Korean actions, but the difficulties the United States had targeting Saddam Hussein in the opening stages of the Iraqi War vividly illustrate the difficulties it would face in targeting the North Korean leadership. Years of building underground structures at some 30 known locations as well as presumably additional unknown ones makes the targeting extremely difficult. Even high precision conventional weapons would be expected to produce minimal results. Nuclear weapons can cause severe damage to underground facilities, but have several drawbacks. Even high-yield weapons (say, 200 kilotons) would have to be reasonably close to the actual command center and in any case could not be expected to be effective against centers over 100 meters deep. So while the general location and entrances of an underground complex may be known, the exact location of critical elements inevitably has a large amount of uncertainty. Furthermore, any nuclear attack would necessarily produce large amounts of fallout. Even an underground burst can be expected to immediately vent to the atmosphere, especially since tunnels themselves would provide a vent pathway. A comprehensive nuclear strike would certainly disrupt North Korean operations but is unlikely to decapitate the command structure.

- Weapons of Mass Destruction (WMD). In addition to its claim to have nuclear weapons, North Korea is generally assessed to have both chemical and biological weapons. Eliminating the threat that these weapons pose would be a formidable task.

* Delivery Systems. These would be the highest priority targets, and eliminating them would be essential to neutralizing North Korea's WMD threat.[18] Some 420 fighters, bombers, transport planes, and helicopters were redeployed in October 1995, with more than 100 aircraft moved to three air bases near the DMZ. As part of this redeployment, more than 20 Il-28 bombers were moved to Taetan which shortened their arrival time to Seoul from 30 minutes to 10 minutes. North Korea is also assessed as having some 500 mobile SCUD and perhaps 100 more modern missiles with ranges over 1000 km. The mobile launchers can move between various deployment positions and are expected to be in reinforced shelters. In addition, biological or chemical agents could be dispersed by hundreds of helicopters, light aircraft, or artillery shells. Just using precision conventional weapons to strike well over 500 hardened shelters for aircraft and missile launchers would be a sizable task and would probably leave a significant percentage of targets still operational. Using low-yield nuclear weapons could increase the kill rate and would allow several positions to be struck with one weapon. But even figuring ten targets per weapon, 50 nuclear strikes, many close to the DMZ, would result in widespread contamination and still leave untouched hundreds of smaller delivery vehicles, as well as surviving attack aircraft and longer range missiles.

* Storage sites. Kanggye No.26 General Plant is the largest underground facility in North Korea -- approximately 10-20,000 workers there manufacture a wide variety of munitions.[19] Kanggye is apparently one of two primary chemical munition assembly facilities, with the other being located at Sakchu. Underground facilities in nearby Chagang Province are reportedly used for manufacturing nuclear warheads or storing plutonium. Anbyon and Masan-dong have been identified as primary chemical weapons storage facilities, with numerous underground storage tunnels dug into mountains. At least a dozen such facilities have been identified and they would provide depot-level storage. Operational weapons would be held by military units in dozens of local storage sites, undoubtedly concealed and hardened. It is highly unlikely that all or even most storage sites have been identified. And even those that are definitely identified no doubt have critical weapons in heavily reinforced locations. Conventional weapon attacks would have little chance of a high kill rate; nuclear attacks would have a higher kill rate but at the cost of still more contamination, particularly since hardened underground locations with uncertain aim points would require ground or subsurface bursts of higher-yield weapons. A single weapon on any one site would severely disrupt activities, but would be unlikely to actually destroy more than a fraction of actual stocks.

* Production facilities. Eight probable chemical production sites have been identified, as well as several suspected biological research and production facilities.[20] These are relatively soft targets, vulnerable to precision conventional weapons. Such strikes would certainly result in local agent releases. Chemical releases would dissipate long before reaching friendly forces. Biological agent releases pose a more challenging situation as local disease outbreaks could eventually spread to a lot larger population. As for nuclear facilities, several major ones are well known, particularly Yongbyon, which has both an operating 5 MW research reactor (currently North Korea's main source of plutonium) and a plutonium processing facility.[21] Several much larger reactors are planned or in various stages of completion, though construction activities have mostly stopped with the on-going international controversies. Attacking operating reactors can pose considerable risks; there are three precedents: Osirak, Chernobyl, and Tuwaitha:

# On June 7, 1981, Israeli fighter jets destroyed the Iraqi Osirak (Tammuz-1) reactor. This was then under construction; the time of the attack was specifically chosen to take place before any nuclear fuel had been loaded. Such a nuclear charging of the reactor would certainly have made a strike much more problematical.[22]

# On April 25-26, 1986 the world's worst nuclear power accident occurred at Chernobyl, 80 miles north of Kiev. During testing at reactor number 4, numerous safety procedures were disregarded; the reactor went out of control, creating explosions and a fireball which blew off its heavy steel and concrete lid. This accident clearly showed the potential results of explosions at an operating reactor; hundreds of square miles are now permanently uninhabitable.[23]

# On January 18, 1991, during the Gulf War, US sea-launched Tomahawk cruise missiles and laser-guided bombs struck facilities at Tuwaitha (the site of the earlier Israeli attack on Osirak). Two operative research reactors were destroyed, as well as one production unit with two hot cells. This resulted in some release of radiation and the facility was afterwards closed for two days. US military spokesmen said that they had detected no radiation release from the bombing. Apparently the Iraqis had shut down the reactor and moved some nuclear fuel to a safer location before the hostilities began and the strike did not destroy reactor cores.[24]

# These precedents show that strikes on a small research reactor may possibly be carried out without major contamination, but destruction of a major power reactor would be another matter. One study shows that a conventional explosive attack on a 1000 MW power reactor could spread high levels of contamination for over 150 miles[25] -- this could certainly provide the United States an incentive to strike reactors before they could be completed. Although the one operating reactor is relatively small, it would certainly be difficult to destroy with any assurance of limited contamination. Any future completion of the larger power reactors would make strikes infeasible.

* Overall, the total North Korean WMD system seems to be far beyond the stage that any sort of "surgical" or even preemptive strike is feasible. And even if nuclear weapons were used in a neutralization effort, the obvious role for any high-yield weapons is very limited.

- Critical military facilities. In addition to command and control, infrastructure, and WMD elements addressed above, several specific types of targets deserve some specific attention.

* Airfields. Aside from the threat posed by the strike aircraft (discussed above), the airfields themselves are important targets, with aircraft stationed at some 20-30 individual bases.[26] Much of the support equipment (radars, fueling facilities, etc.) could be engaged by precision conventional weapons, but the runways are very difficult targets. Craters from conventional weapons can be rapidly filled in. Nuclear weapons can cause severe long-term damage in two ways. They can heave the earth under the runways, but then an effective strike would require surface penetration -- not an easy task when dealing with reinforced runways. Alternatively, a ground burst on the runway itself would produce major cratering. But such ground bursts also would produce widespread contamination. Furthermore, even such strikes would probably have limited military impact because North Korea has dozens of alternative runways, including specially prepared highway strips.

* Air Defense systems. These are also priority targets to provide US aircraft with free use of North Korean airspace. Such systems were among the priority targets at the start of the Iraqi War and certainly would be a priority in North Korean operations. They can be effectively engaged by precision conventional munitions, but obviously weapons targeted at these facilities in an initial strike would not be available for other priority targets. The bulk of North Korean radars are older Soviet and Chinese models with vacuum-tube technology, which limits continuous operations. The overall early warning and ground controlled intercept system is susceptible to saturation and jamming by a sophisticated foe with state-of-the-art electronic warfare capabilities. Nevertheless, the multilayered, coordinated, mutually supporting air defense structure is a formidable deterrent to air attack. With over 8,800 antiaircraft guns, as well as SA-2/3/5 and handheld SA-7/16 surface-to-air missiles, North Korea has constructed one of the world's most dense air defense networks. Individual targets are in the hundreds, with at least 50 major command, missile, and radar installations.[27] Nuclear targeting would of course facilitate system neutralization; lower-yield air bursts would be adequate for many of these targets, although command centers would probably require higher-yield strikes, probably with ground or subsurface bursts.

* Major troop garrisons. Unfortunately, there are not five major garrisons, but hundreds of smaller ones. They are all clearly vulnerable to conventional strikes, but in any crisis situation troops would be deployed in the field. Troop concentrations closer to Seoul would certainly be a relative priority and a large percentage of potential North Korean attack forces are in this general region. Their nearness to Seoul increases the urgency of the threat they pose and consequently the priority for engagement. Small-yield nuclear weapons could be militarily very useful, but these are exactly the weapons which were withdrawn in 1991. Furthermore, any nuclear weapons use close to Seoul would pose substantial contamination problems for the South Koreans, although enhanced radiation weapons could reduce the problem. At most, a selective use of lower-yield weapons on the most menacing troop formations might be considered.

 

Target type

 

Target

Points

WEAPON USE

 

Comments

Low

Yield

High

Yield

Ground

Burst

 

 

 

 

 

 

Major cities

7

7

 

 

 

Infrastructure

50

50

 

 

Priority targets with immediate impact

Command & Control

30

 

30

yes

Uncertain results, high contamination

WMD Systems

 

 

 

 

 

- Delivery

50

 

 

?

Marginal effectiveness

- Depot Storage

12

 

12

yes

Limited immediate impact

- Field Storage

?

?

 

 

Difficult to identify target points

- Production

 

 

 

 

 

* Chem/bio

10

10

 

 

Agent releases

* Nuclear

5

?

 

 

Contamination considerations complicate targeting

Critical Military Systems

 

 

 

 

 

- Airfields

30

30

 

??

Bases with aircraft stationed

- Air defense systems

50

45

5

yes

Including hardened command centers

- Troops

10

10

 

 

Selected very high priority units only

Table 1. Potential Nuclear Targets - North Korea

Table 1 summarizes potential nuclear targeting. Conventional weapons would be generally ineffective against the most critical targets (command and control centers and WMD delivery vehicles). Engaging these targets with nuclear weapons would not only require large numbers (well over 100), but even then effectiveness is questionable because of target hardening and uncertainties on locations. Neutralization to a high degree of confidence of North Korean command and WMD capabilities seems well out of reach, even with a US use of nuclear weapons, so potential North Korean retaliation (particularly against Seoul) cannot be reliably eliminated.

Using nuclear weapons would necessarily result in widespread nuclear contamination and large numbers of causalities. Nor would it be possible to limit this to the Korean peninsula alone. High air bursts would minimize fallout, but also insure that it carried a maximum distance (i.e., across neighboring countries). Higher yield ground bursts (required for many of the hardened facilities) would release much more fallout. Even limiting their use to the most critical probable command centers, perhaps a dozen, would still produce unacceptable levels of fallout. Anything less would certainly be ineffective. Lower-yield, deep penetrating warheads, even if available would be inadequate because of the difficulty of specifying an exact underground location to engage.

It is clear that rapid neutralization of the North Korean WMD capabilities or incapacitation of the leadership cannot be achieved with conventional weapons. But the use of nuclear weapons would require relatively large numbers, would produce significant fallout, and would still provide only a low assurance of success. And even in these extreme circumstances, the only clear requirement for high-yield strategic nuclear weapons would be on some selected command and control facilities; their use would have to be restricted to a small number of targets because of fallout considerations. In the event of large-scale hostilities, the number of potential targets climbs into the hundreds. Such a widespread use of nuclear weapons on the small Korean peninsula not only seems most unattractive, it would almost certainly provoke North Korean retaliation with their own remaining WMD.

Use of a relatively few nuclear weapons against carefully selected targets would minimize contamination, but would also minimize results and still raise the specter of North Korean retaliation.

Overall, it seems difficult to construct scenarios where any nuclear strikes would be appropriate; even a battlefield use of nuclear weapons seems unappealing. Furthermore, current counterproliferation planning emphasizes the use of lower-yield weapons, including specially designed earth-penetrating weapons.[28] So even if a high-yield requirement somehow developed, a handful of strategic weapons would certainly suffice.

IRAN

Iran is another potential nuclear opponent. The United States remains very suspicious of its nuclear programs, which Iran claims are strictly for peaceful use.[29] Despite extensive international pressure, Iran insists on a right to enrich uranium. In regard to potential US counteractions, President Bush has specifically stated that "all options" are open.[30]

But assuming Iran did develop nuclear weapons and for some reason decided to use them, they also would pose little threat to the United States itself, at least for a number of years.

Targeting Iran faces an entirely different set of considerations than actions against North Korea. But, as with North Korea, even an initial overview shows that military options are very restricted and the usefulness of high-yield strategic nuclear weapons is very limited. Major considerations with Iran include:

- Weapons of Mass Destruction (WMD). Iran insists that is has no nuclear weapons and is not trying to produce them; Western reviews dispute this, but estimate that such production would take five to ten years.[31] Iran apparently also has chemical and possibly biological weapons.

- Intelligence. Iran is not nearly so impenetrable as North Korea. However, intelligence failures prior to the Iraq invasion underline how difficult it can be to get good information in this area of the world and then to accurately assess it. One recent evaluation concluded that US intelligence knows "disturbingly little" about Iran.[32]

- Hardened facilities. Iran does not have anything even vaguely resembling the extensive North Korean tunnel system, although Iran has recently been tunneling just north of its uranium conversion facility at Isfahan. In the words of one Iranian official, "From the moment the Americans threaten to attack our nuclear sites, what are we to do? We have to put them somewhere." Iran had also managed to keep a fairly extensive research and pilot program secret from the international community for a number of years. Nevertheless, it is clear that most facilities are soft targets and that deep targeting requirements are much smaller than with North Korea.

- Damage recovery. The burden of any post-strike recovery would not fall on any US ally. Rather, if Iranian policies resulted in US strikes, it is Iran itself that would bear the brunt of reconstruction costs.

- Fallout. This is the same problem that nuclear strikes in North Korea would pose. Iran is a larger country, but is surrounded by many more countries than North Korea, including former Soviet countries on the north, Afghanistan and Pakistan on the east, and to the north and west not only Turkey and Iraq, but a whole range of countries and emirates across the Persian Gulf.

- Hostage Cities. There is no local equivalent to Seoul, a major allied city within easy striking distance of Iran. There are some US military units and facilities in both Afghanistan and Iraq. Israel is within range of some Iranian missiles and is certainly considered by many in the Iranian leadership as a US partner.

- Allied objections. Three European countries (Germany, France and Great Britain) are heavily engaged in negotiations with Iran and strongly opposed to any military action, all the more since unilateral US intervention in Iraq has proved so costly and the threat from Iran is not a pressing one. The German Chancellor, for example, recently commented "take the military options off of the table ... they're not suitable."[33] Iran has also been actively working to get additional countries involved in the negotiations. In addition, Russia has been expanding its relationship with Iran, including long-standing cooperation supplying military equipment and civilian nuclear technology and has specifically declined to support U.N. actions against Iran.[34] As with North Korea, any strikes with long-range strategic weapons might well require overflights of other nations which would be unlikely to provide permission.

- Beleaguered leadership. Although much of the Iranian public appears to be unhappy with the tight theocratic controls, US actions against the government would probably considerably strengthen its popular acceptance. The leadership clearly does not feel itself threatened and is committed to promoting Shiite Islam. Further, in any crisis situation, the leadership would have incentives to negotiate, so its elimination would not necessarily be an objective.

- Threat misperceptions. As with North Korea, distant launches could be mistakenly identified by Russia or China as incoming strikes and cause them to initiate some sort of counter-actions against the United States.

- Iraq. The unsettled situation in Iraq also greatly complicates the overall US-Iranian relationship. Already there have been at least suspicions that Iran is aiding Shiite extremists within Iraq. Certainly it has an ability to promote Shiite opposition to US troops and to a central Iraqi government. So one consequence of any direct US actions against Iran would certainly be a serious destabilizing of any Iraqi government. On the other hand, a bit further in the future, Iran could well develop close ties with a Shiite-dominated Iraqi government which certainly would not support US strikes on Iran. Cooperative military actions have already begun, led by the Iraqi Defense Minister, a Sunni.[35] Depending on the flow of future events, such an alliance could be strongly anti-American and undermine US efforts throughout the Middle East.

- Oil. Economically, North Korea is a basket case, while Iran is swimming on a sea of oil in a world of rapidly rising oil prices. This situation not only makes economic sanctions against Iran inherently ineffective, but also buys strong support to Iran from China whose own oil requirements continue to rise dramatically.

Against this background, a first overview will consider the same types of engagement scenarios and major target sets as for North Korea.

Engagement scenarios include:

- Retaliation. Iran does not have nearly the capability for a major strike on US interests that North Korea has. The largest threat might be a strike on Israel, but Israel has shown itself well capable of its own retaliatory strikes. Nevertheless, some unforeseen developments might call for a major US military response .

- WMD neutralization. Threats of Iranian WMD are mainly set in some future period when Iran may hold nuclear weapons. The United Sates may also consider preemptive neutralization, eliminating delivery systems, military stocks, and/or research or production facilities.

- Leadership incapacitation. This could certainly be an immediate objective in case of some military actions, but does not seem to have near the urgency that it would have in a North Korean crisis.

- Military neutralization. This would require elimination of key military facilities and infrastructure.

- Comprehensive engagement. This would require essentially a combination of all of the above. It would be a major war situation in response some kind of momentous Iranian provocations. But even in this situation, some sort of major land war seems highly unlikely. There is certainly no adjacent US ally that would be ready to occupy the country as is the case with North Korea.

Target sets for these scenarios include the following:

- Major cities. Tehran, with a population of over six million, as well as Mashad with well over a million and Esfahan, Tabriz, and Shiraz, all of which are near one million, are the largest. Altogether there are over 30 cities with populations exceeding 100,000. But it is hard to envision any scenarios which would focus on urban destruction. Further, as soft targets, these cities could be devastated by relatively small nuclear weapons. There is no conceivable requirement for high-yield strategic weapons to attack Iranian urban targets.

- Infrastructure. A concentrated conventional attack on Iranian infrastructure (major bridges, rail yards, power generation and transmission facilities, telecommunications centers, industrial plants, and fuel depots) could certainly destroy the Iranian economy. Numbers are certainly larger than for North Korea. These are almost all soft targets susceptible to attack by conventional weapons. Attrition of infrastructure could conceivably be used to pressure the government (as was done with Serbia). Only in extreme cases would any use of lower-yield nuclear weapons be at all attractive.

- Command and control. Iran's key leaders are religious figures, so targeting the national leadership necessarily means targeting major religious centers. Such an action could only result in a firestorm of opposition throughout the Muslim world; this makes any specific targeting of the Iranian national leadership impractical. At a lower level, the Joint Staff of the Ministry of Defense, with its subordinate Islamic Revolutionary Guard Corps as well as an Operational Area Command and several field headquarters could certainly be targeted.[36] Some of these may be in hardened locations, but the biggest targeting challenge would undoubtedly be identifying exact locations, especially in a time of crisis. Conceivably, attacks on some identified, hardened command centers could be carried out with nuclear weapons.

- Weapons of Mass Destruction (WMD). In addition to its nuclear programs, Iran is estimated to have an inventory of several thousand tons of various chemical agents capable of delivery by artillery and bomb systems, and possibly by Scud missiles.[37] It also has a capability to produce biological weapons, but seems to be only involved in research at this point.

* Delivery Systems. These would be the highest priority targets, and eliminating them would be essential to neutralizing Iran's WMD threat, at the moment primarily a chemical weapons threat. The US weapon embargo since the Iranian Revolution has severely degraded Iran's air force. Perhaps 150 older fighter aircraft remain operational; these have been augmented by some more modern Russian military aircraft. Neutralization would require multiple strikes at some 14 airbases. [38]Nuclear weapons would be much more effective than conventional ones, but aircraft dispersal in a crisis situation would greatly complicate targeting.

* Storage sites. Iran strongly denies producing or possessing chemical weapons. Open source reports of Parchin as a major chemical weapons facility, along with the facilities located at Damghan, Esfahan and Qazvin are of uncertain reliability.[39]

* Production facilities. In addition to the four chemical sites just mentioned, there are approximately two dozen nuclear-associated sites, ranging from research facilities to an enrichment facility at Natanz, research reactors at Ishfahan, and a developing power reactor complex at Bushehr[40]

* Overall, the total Iranian WMD system is much less developed than the North Korean one. From a proliferation point of view, the enrichment facility is of particular concern. Although most of the facilities are relatively soft targets, the difficulty of bringing large numbers of conventional weapons to bear deep within Iran could make use of nuclear weapons more attractive. One notional evaluation of such a strike involved ten facilities, each targeted by three smaller-yield (10 KT) weapons. Such a strike would basically destroy the Iranian nuclear system, but would cause probably two million deaths and wide contamination.[41] Even in this extreme case, any role for strategic weapons would be very limited. A less damaging strike of one nuclear weapon each on ten target points would still produce major casualties and widespread contamination, but would also have much more limited results.

- Critical military facilities. These would include:

* Airfields. A total of 14 air bases are currently operational. In addition, Iran has several hundred older SCUD missiles with ranges up to 500 kilometers. Extensive cooperation with North Korea and China have led to development of longer range missiles, including a Shehab-3 based on the North Korean Nodong missile with a range of 1300 kilometers and an inventory of at least 25.[42] More recently, Ukraine was reported to have sold Iran a dozen cruise missiles boasting a highly accurate guidance system and a range of up to 3,000 km.[43] Potential targets would include the Shahroud missile range as well as several other launch facilities. None of these facilities are hardened like the North Korean facilities, so conventional weapons could do serious damage. Runway destruction could require nuclear strikes, but the presence of numerous alternative civilian airfields makes this an unattractive option.

* Air Defense systems. Iran does not have a nationwide, integrated air defense network, and continues to rely on point defense of key locations with surface-to-air missile batteries. By the mid-1990s, Iran's total holdings seemed to include 30 Improved Hawk fire units, 45-60 SA-2 and Chinese equivalents, as well as perhaps 25 Russian SA-6 launchers.[44] There are also unverified reports of Soviet-made long-range SA-5 units, with a total of 10-15 launchers -- enough for six sites.[45] In total, this is not a very robust capability, but some of the missiles are mobile and this of course complicates targeting. Altogether there are perhaps 20 sites that could be targeted plus some command and control and radar installations; low-yield nuclear weapons would be one option.

* Major troop garrisons. Iranian troop concentrations are of a much lower concern than North Korea's since they do not actively threaten any US ally. A confrontation with some new government in Baghdad is theoretically possible, but highly unlikely given that Iraqi Shiites will almost certainly play a major role in any new Iraqi government. In the more distant future, Iran seems determined to become a power in the Middle East and some sort of ground threat might develop. At the moment, there is none in sight.

POTENTIAL NUCLEAR TARGETS -- IRAN

 

Target type

 

 

Target

Points

WEAPON USE

 

Comments

Low

Yield

High

Yield

Ground

Burst

 

 

 

 

 

 

Major cities

5

0

 

 

Unlikely targets

Infrastructure

75

10

 

 

Priority attrition targets, limited nuc use

Command & Control

10

 

10

yes?

Military centers only

WMD Systems

 

 

 

 

 

- Delivery

42

?

?

 

Marginal effectiveness if dispersed

- Depot Storage

4

4

 

yes?

Limited immediate impact

- Field Storage

?

 

?

 

Difficult to identify targets

- Production

 

 

 

 

 

* Chem

5?

?

 

 

Potential agent releases

* Nuclear

10

10

 

 

Contamination considerations

Critical Military Systems

 

 

 

 

 

- Airfields

14

14

 

??

Military airbases only

- Air defense

25

20