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Weapons of Mass Destruction (WMD)

Neutron Bomb / Enhanced Radiation Weapon

An enhanced radiation (ER) weapon, by special design techniques, has an output in which neutrons and x-rays are made to constitute a substantial portion of the total energy released. For example, a standard fission weapon's total energy output would be partitioned as follows: 50% as blast; 35% as thermal energy; and 15% as nuclear radiation. An ER weapon's total energy would be partitioned as follows: 30% as blast; 20% as thermal; and 50% as nuclear radiation. Thus, a 3-kiloton ER weapon will produce the nuclear radiation of a 10-kiloton fission weapon and the blast and thermal radiation of a 1-kiloton fission device. However, the energy distribution percentages of nuclear weapons are a function of yield.

While the names of Albert Einstein and Edward Teller and Robert Oppenheimer are associated with the development of the atomic bomb, a relatively unknown scientist is credited with being the father of the neutron bomb. He was Samuel Cohen, who came up with the concept of the neutron bomb in the late 1960’s while working for the Rand corporation. He was recruited as a researcher for the Manhattan Project, which developed the first atomic bomb.

A specialist in the radiological effects of nuclear weapons, he relentlessly promoted the neutron bomb for much of his life, writing books and articles, conferring with presidents and cabinet officials, taking his case to Congressional committees, scientific bodies and international forums.

The New York Times noted "Washington rejected the bomb repeatedly. The Kennedy administration said it might jeopardize a test-ban moratorium. The Johnson administration said its use in Vietnam might raise the specter of Hiroshima — Asians again slaughtered by American nuclear bombs — drawing worldwide condemnation. In 1978, President Jimmy Carter said development might impede disarmament prospects."

During the late 1970s under a strict budget imposed by Congress, Sandia began developing the W82 design for artillery shell that could be fired by the 155-millimeter howitzer by the Army and NATO forces. Don Bohrer and Bill Wilson managed this project for Sandia with Dennis Beyer and Jack Martinell as the lead engineers for the design of the structural case as well as the arming and firing components.

The biggest challenges were to pack a sophisticated weapon insde a round only about six inches across and to protect it from the severe gun loads as the round is fired from a howitzer's rifled barrel. And it had to have the same ballistic characteristics as a conventional round. Finally, it had to meet strict budgetary requirements. Sandia's earlier experiences in the design of the W79 eight-inch round proved useful in designing the W82 and helped to contain development costs.

President Gerald Ford in April 1976 approved the enhanced-radiation warhead. What made the neutron warhead appear soemwhat insidious was the alleged employment of secrecy to slip it past an unwary President and Congress. On 21 June 1977, an article in the Washington Post headlined "Senate Pressed for Killer Warhead" stated that "Neither President Carter nor Defense Secretary Harold Brown knew that money for its production was in the fiscal 1978 budget they had reviewed until news reports appeared two weeks ago.'" On 24 June, Post readers learned that "The Pentagon is proceeding in great secrecy to produce neutron 'killer' shells for its nuclear artillery forces in Europe." On 25 June, the Post headlined an article: "Pentagon Wanted Secrecy on Neutron Bomb Production." In a follow-up article on 01 July, the Post, following a lead from the Pentagon, now referred to the warhead as an "enhanced radiation weapon" and quoted freely from an Army publication to graphically describe how radiation kills.

Congress was divided on the issue. On 01 July, Senator John Stennis told reporters that the neutron warhead was "the best news I have heard in years." But Senator John Heinz found the weapon "even more repugnant than usual ... literally dehumanizing." Senator Mark Hatfield, who was to lead Senate opponents of the warhead, declared that "Everything up to this point has been more by discovery than by information. We discovered that it was in the budget. We discovered that no President had ever approved it. This whole thing has stumbled into our life." He concluded that "My ultimate hope is that this weapon never enters the arsenal."

The neutron bomb was a misnomer created by Walter Pincus of The Washington Post in the summer of 1977 and then applied to the W79 and W70-3 warheads for the 8-inch and Lance systems, respectively. The correct terminology for the W70-3 and W79 warheads is "reduced blast/enhanced radiation (RB/ER) warheads" not "neutron bombs." Lance and 8-inch warheads were already in Production Engineering at the time that the RB/ER warheads first came to public notice on 6 June 1977.

The Washington Post story immediately triggered widespread debate in the United States and abroad. Despite the fact that both had been approved and funded by the President and Congress for several years, the ER warheads quickly became a political albatross to the Carter Administration. Abetted by the furor created overseas by NATO allies and the Soviet Union, DOE's FY 1978 Authorization Bill contained the Byrd-Baker Amendment which gave Congress 45 days to veto any production decision by the President who would have to state that the production of ER warheads was "in the national interest."

In effect, there followed a complete halt to the ER warhead development for one year. Regardless of the problems and frustrations this stoppage caused both the Departments of Defense and Energy, it took over one year for the Administration to "test the waters" and decide not to decide the question of production and deployment of ER weapons. On 7 April 1978, President Carter made a public statement on the resumption of production activities. It wasn't until six months later, however, that DOD and DOE received any clarification of exactly what the President had in mind in his April statement.

The Pincus article in The Washington Post had at least one useful consequence: It forced intense public review of the fundamental issues regarding nuclear weapons production and deployment. Senator Hubert Humphrey in a major Senate debate on ER weapons on 13 July 1977, said: ". . . we have . . . blown this weapon out of all proportions." Whether the pun was accidental or deliberate is not recorded, but the statement is certainly accurate.

Death and destruction are not novelties to the soldier, but neither were they introduced into the world by the advent of ER weapons. "Ordinary" nuclear weapons would lead to identical or worse death and destruction than ER weapons with the possible exception that the victims might well be more innocent and numerous. Many participants in the ER controversy have expressed hostility to ER weapons on alleged ethical grounds. The complaint is that it is immoral to have a weapon that would kill people but not destroy property. This so-called ethical part of the argument is unrealistic. Bows and arrows are even less effective at destroying property, but they kill people quite handily. Yet, it has never been alleged that this is a moral defect of bows and arrows. It cannot be argued that the unwanted destruction of property, even if personnel are not involved, is somehow a moral good.

The ethical argument also overstates the reduction in blast or other nonneutron effects that ER weapons provide. Such effects would be reduced by a factor of 10 for ER weapons compared to standard fission weapons of the same effectiveness. But, when dealing with energy yields of thousands of tons of TNT, a factor of 10 — while important — should not be confused with the difference between night and day.

The Soviets had time and opportunity to initiate a worldwide campaign to pressure President Carter. The Soviets peace campaign began in 1977 in reaction to the enhanced-radiation warhead (ERW), which soon was labeled the neutron bomb.

Since 1977 a major campaign of the World Peace Council was against the neutron weapon. This weaponwhich can be used against tanks but would leave the sur-rounding civilian areas intact, could remove the imbal-ance in Western Europe threatened by the massive Soviettank army in East Germany. It is vitally important for theSoviet Union and its international fronts to prevent thedevelopment and deployment of the neutron weaponwhich would remove so powerful a force from the Soviet arsenal threatening Western Europe.

The Soviet press began July 9, 1977, with a cry from TASS aimed at Carter himself: “How can one pose as a champion of human rights and at the same time brandish the neutron bomb, which threatens the lives of millions of people?" The Kremlin then warned the world that the neutron bomb can “only bring the world closer to nuclear holocaust." Throughout July the Soviet press and radio, in an ever-rising chorus, sounded variations of this refrain: The ghastly new American weapon, the neutron bomb, threatens mankind with nuclear extinction. To be for the neutron bomb is to be for war. To oppose the neutron bomb is to be for peace. The state-controlled media of Eastern Europe and the newspapers of communist parties in Western Europe faithfully echoed the party line emanating from Moscow.

Initially, the Active Measures against the ERW were mostly overt and the propaganda was traceable to communist sources. But in August 1977 the campaign advanced into semi-covert and clandestine phases. The [Soviet controlled] World Peace Council proclaimed August 6–13, 1977, a Week of Action, and its front groups, aided by the KGB and local communist parties, promoted public demonstrations whose Soviet sponsorship was less evident.

Crowds pleading in the name of humanity against the “killer neutron bomb," demonstrated before US consulates or embassies in Bonn, Stuttgart, Frankfurt and Istanbul. The demonstrators — in Germany and the Netherlands at least - were mostly non-communists attracted by intensive advertis ing, and motivated by a variety of impulses: anti-Americanism, pacifism, abhorrence of all nuclear weapons and a sincere longing for peace.

The theme that the "neutron killer warhead" was "antipeople," that it is more "inhumane" than other nuclear weapons, was repeated in numerous press accounts in the summer of 1977. . In an editorial in the Post on 8 June, it was described as a "precise killer" which could be construed as a "grisly" chemical and biological weapon, and "just about the last thing anyone should want for the American arsenal." An editorial in The Christian Science Monitor on 18 July 1977 included the comment that "There is no question the neutron bomb, which is designed to wreak more destruction on people than property, is morally abhorrent."

In June 1977 President Jimmy Carter announced a delay in the final decision until November 1977. In October 1977, Secretary of Defense Harold Brown announced President Carter would approve pro- duction of the ERW only if NATO allies agreed in advance to its deployment on their territories. Western European leaders recognized the ERW as a much safer, more credible deterrent than the nuclear warheads already on their soil, and privately wanted it added to NATO defenses.

By temporizing and publicly shifting the burden of decision to them, Carter exposed Allied leaders as well as himself to intensified pressures. Accurately assessing Carter as a devoted Baptist, the Russians played upon his deep religious faith. In a dispatch quoted by the American press, TASS reported: “Soviet Baptist leaders today condemned production of the neutron bomb as 'contrary to the teachings of Christ' and urged fellow Baptists in the United States to raise their voices in defense of peace.”

In September 1977, the World Peace Council published a pamphlet entitled “Neutron Bombs No!". Its slogan was 'In the name of life itself, ban the neutron bomb'. The introduction to the pamphlet was written by Romesh Chandra. According to Chandra, "The worldwide campaign launched bythe World Peace Council in August 1977 for the prohibition of the neutron bomb is the most powerful mass movement of recent times against weapons of mass destruction and for the ending of the arms race. The call of the World Peace Council has been supported actively by numerous international and national organizations representing literally tens of millions people in all countries."

He went on to say, "In the NATO countries the protest movement has grown as the holiday period has come to an end: in each country actions are specially directed towards demanding that the government concerned declare publicly its opposition to the placing of neutron bombs on its territory and demands that President Carter abandon his perilous policy of stepping up the arms race. In the socialist countries the campaign against the neutron bomb embraces the entire population and continues in ever new forms. In Asia, Africa, and Latin America the protest actions against the neutron bomb have grown remarkably in a number of countries. The World Peace Council has called for the continuation and the intensification of the protest actions to ban the neutron bomb.'"

The World Peace Council appeal, carried in the same pamphlet, said, “The Bureau of the Presidium of theWorld Peace Council meeting in Berlin, September 9 to 12,welcomes the world protest against the neutron bomb - a torture weapon being cynically presented as a so-called' clean bomb by the United States administration.'

The appeal went on to say, "the Bureau urgently calls for worldwide actions during the fortnight from October 1-15 Against the Neutron Bomb and All Other Weapons of Mass Destruction ... The Bureau calls upon all national peace committees, peace forces, political parties and other national, regional, and international movements and organizations to raise the alarm about these new dangers by organizing: mass rallies,meetings, demonstrations, delegations, petitions to parliamentarians, legislators, governments and heads of state, leaflets, publications and wide spread use of the mass media. We urge letters of protest especially to the President of the United States against the development of the neutron bomb.'

Among the organizations whose statements against the neutron weapon found in the WPC pamphlet were the following international Soviet fronts: The World Federation of Trade Unions, The Christian Peace Conference, the Women's International Democratic Federation, the International Union of Students, and the World Federation of Democratic Youth.'

From January 25-28, 1978 the Bureau of the World Peace Council met in Washington, DC. The place was chosen very carefully. Its major agenda item was clear. AWPC report said, 'A special session of the Bureau was dedicated to the review of the campaign to Ban the Neutron Bomb. Reports made to the Bureau showed thewide and broad nature of the campaign.'

Washington, DC as a site of this meeting was useful in getting as much publicity as possible in the United States for the campaign against the neutron weapon. On May 22, 1978 the World Peace Council took advantage of the United Nations special session on disarmament which had been promoted by the Soviet Union and the Communist bloc to present what they claimed were 700 million signatures on disarmament to the UN Secre-tary-General Kurt Waldheim. In a statement presented with the signatures the WPC complained about the American development of the neutron weapon and the stationing of cruise missiles in Western Europe.

On June 3 and 4, 1978, the World Peace Council organized a meeting of parliamentarians in New York City supposedly in support of the special session of the UnitedNations General Assembly on Disarmament. The meeting of parliamentarians "declares that the production of theneutron bomb accelerates, in a tragic fashion, the arms race.' It went on to say, 'This meeting appeals to parliamentarians and all other elected representatives of thepeople to reject the fabrication and deployment of the neutron bomb.'

The WPC newsletter Peace Courier was filled with stories of protests against the neutron weapon. In West Berlin the Communist Party, which there calls itself the 'Socialist Unity Party, West Berlin,’ issued to its members a collection of articles from publications around the world attacking the neutron weapon. This collection was designed to be used in agitation against the neutron weapon during demonstrations in West Berlin. It takes careful examination of the documentation to realize that most of it came from Communist sources.

In January 1978 Brezhnev sent letters to the heads of all Western governments asserting that the neutron bomb would “pose a grave threat to détente.” Western members of parliament received similar letters from members of the Supreme Soviet and Soviet trade-union leaders.

President Carter's three principal foreign- policy advisers — Secretary of State Cyrus Vance, Secretary of Defense Harold Brown and National Security Adviser Zbigniew Brzezinski — all urged production. So did the Washington Post and the New York Times. Declared the Times: “Ever since the Carter Administration asked Congress last summer for funds to produce enhanced- radiation nuclear warheads, critics ranging from Soviet propagandists to Western cartoonists have had a field day attacking the so-called 'neutron bomb.'"

A Presidential decision was announced in simultaneous White House and DOE press releases on 17 October 1978 and confirmed the statement of 7 April 1978 but, did not address deployment to Europe. The decision directed DOE to:

  • Modernize Lance missile warehead with W70-3.
  • Modernize 8-inch howitzer shell with W79.
  • Deliver new warheads to Defense Department without the enhanced radiation features.
  • Be prepared to add an enhanced radiation capability if directed to do so.

So while DOE resumed production engineering of the new warheads in FY 1979, it was clear that the W79 and W70-3 warheads would be "emasculated" versions of the original designs. Through the efforts of the designers, Sandia and Lawrence Livermore Laboratories of California, a way was devised to add the ER capability, if directed at a later date. Army officials however were so anxious to get on with it after a one-year delay that they were willing to tell Congress that even without a fielded ER capability, they wanted the new warheads anyway. The current 8-inch projectile was such an example; its short range and ballistic simulitude deficiencies and lack of modern safety, security, and reliability features caused the Army to accept the ER "convertible" warheads, thinking perhaps that a different President could be convinced to convert to the ER capability.

It is interesting to note that the Lance and 8-inch development had progressed through the Government in a completely ordinary way until the controversy erupted in June 1977. Some have charged that the Administration tried to "sneak" the weapon through Congress, but nothing could be farther from the truth. And none were more surprised than DOD and DOE at the magnitude of the storm that broke; it was such a storm that might arise, say, over the decision to replace one model of tank by another.

The US continued development of enhanced radiation weapons - the neutron bomb as it is called - but deferred decisions about production and deployment of these system. President Carter stated these decisions would be influenced by the degree of Soviet restraint in its weapons programs and force deployments which affect NATO security: The intended role for enhanced radiation weapons was short-range tactical use. Decisions about whether to procure such weapons would be taken separatly from those involving long-range theater nuclear weapons.

In 1981, President Ronald Reagan ordered 700 neutron warheads built to oppose Soviet tank forces in Europe. He called it “the first weapon that’s come along in a long time that could easily and economically alter the balance of power.” But deployment to the North Atlantic alliance was canceled after a storm of antinuclear protests across Europe. President George Bush ordered the stockpile scrapped.

NATO's basic strategy was one of flexible response. Its principal putpose was to deter acts of aggression which may range from all-out invasion to demonstrations of force. Flexible response was based on the premise that the most effective way of discouraing enemy action at any particular level of violence was to have an appropriate response to that action at that level of conflict, and having the ability to respond at greater levels of violence will demonstrate to the enemy the risks and costs of continuing the conflict.

Third generation nuclear weapons are “tailored” or “enhanced” effects warheads — such as the Enhanced, Suppressed, and Induced Radiation Warheads (ERW, SRW, IRW), the Reduced Residual Radioactivity (RRR) or Electromagnetic Pulse (EMP) bombs, Hot X-ray devices for antiballistic missile (ABM) systems, “clean” explosives for possible use in peaceful activities — or nuclear-driven “directed energy” devices. For the most part, these ideas never became part of a third generation of nuclear explosives because they never found any truly convincing civilian or military use.

The distinguishing factor of the neutron bomb is that many of the neutrons that are used in building up the chain reaction are instead allowed to escape. The resulting radiation is extremely destructive to matter, slicing through it easily. Up to 80 percent of the power of the explosion is made of the energy of the current of fast neutrons. Other destructive factors make up 20 percent - the blast wave, the electromagnetic impulse and radiation.

Sam Cohen in 1958 investigated a low-yield 'clean' nuclear weapon and discovered that the 'clean' bomb case thickness scales as the cube-root of yield. A larger percentage of neutrons escape from a small detonation, due to the thinner case required to reflect back X-rays during the secondard stage (fusion) ignition. Thus, a 1-kiloton bomb would need to have a case only 1/10th the thickness of that for 1-megaton. This meant that while most of the neutrons were absorbed by the outer casing in a 1-megaton bomb, in a 1-kiloton bomb they would mostly escape. A neutron bomb would be feasible if the yield was sufficiently high for efficient fusion stage ignition, and if the yield was low enough that the case thickness would not absorb too many neutrons.

The neutron bomb was a technological marvel. An ordinary hydrogen bomb consists of several parts. The first stage is a fission device called the "primary," usually a plutonium shell that is imploded into a critical mass. The gamma rays from this primary move with the speed of light and compress the "secondary," a combination of lithium-6 (which rapidly decomposes to tritium and helium) and deuterium. The tritium and deuterium (both isotopes of hydrogen) are compressed by the gammas to release the energy of fusion. Neutrons from the fusion stream out and are captured on a depleted uranium shell (U-238) - the "pusher"- triggering additional fission. About half of the energy of such a weapon comes from this secondary pusher fission. The fission fragments from this uranium shell are also responsible for most of the radioactive debris.

The neutron bomb eliminated the uranium shell [the "pusher"], and made the primary really small. As a result, most of the energy was released in fast and deadly neutrons rather than in heat and blast. This was a bomb that would kill but not destroy — perfect for the defense of West Germany.

A Memorandum From the Joint Chiefs of Staff to Secretary of Defense McNamara, Washington, April 8, 1961, noted that "The principle upon which a “neutron bomb” may be developed has been known to the Soviet Union, by their own admission, since 1952. [3-1/2 lines of source text not declassified] Inherent in the neutron bomb concept — a pure fusion weapon emitting very high intensities of neutrons — is that the only scarce nuclear component required is tritium [4-1/2 lines of source text not declassified].

"b. The major characteristic of the neutron bomb is the extent and range of its lethal instant radiation effect and relatively small other effects as compared to the much larger blast, thermal and residual radiation effects of the fission weapons. This characteristic may make the neutron bomb highly efficient as an anti-personnel weapon without the other destructive characteristics, including radioactive contamination, which are associated with fission weapons. Thus, the new weapon might be classed somewhere between conventional and current nuclear weapons....."

Cohen's neutron bomb was not mentioned in the unclassified manual by Glasstone and Dolan, The Effects of Nuclear Weapons 1957-77, but was included as an 'enhanced neutron weapon' in chapter 5 of the declassified (formerly secret) manual edited by Philip J. Dolan, Capabilities of Nuclear Weapons, U.S. Department of Defense, effects manual DNA-EM-1, updated 1981.

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Page last modified: 12-03-2022 17:29:49 ZULU