Blockades: Determining Effectiveness
Subject Area - Warfighting
TITLE: Blockades: Determining Effectiveness
AUTHOR: Lieutenant Commander C. Troedson, United States Navy
THESIS: Since the decade of the l98O's, blockades have become an
increasingly important weapon of diplomacy in coercing belligerent
nations to accept U.S. or international policy. There are many
considerations the blockading nation must address if success is to
be achieved. The success of the blockade is not always obvious and
is difficult to determine for several reasons.
BACKGROUND: As the most powerful Navy in the world, the US Navy
has been called upon on numerous occasions in the last two decades
to conduct naval blockades. While the Navy is quite capable of
performing the operation there are several key factors which
planners must consider which will promote success. Is the effort
supported both nationally and internationally? Is control of air,
land, and sea routes possible? What are the desired results and
are they achievable through blockade alone? Is the blockaded
nation vulnerable to the blockade. Is the hardship that the
blockade will inflict on non-combatants justified by the expected
results? Blockades are not effective against all countries and a
blanket policy of imposing one for every crisis is wrong. The
blockades imposed upon Iraq and Haiti will be evaluated based upon
RECOMMENDATIONS: The same attention placed upon proper planning for
the air, land and sea battle needs to be applied when considering
imposition of a naval blockade. Determinations need to be made
upfront concerning the goal and expected impact the blockade will
have for the targeted country. To impose an economic blockade
blindly without considering the economic and political situation of
the blockaded nation may result in failure to achieve the desired
A blockade cannot be classified as a surgical strike or
even as a smart weapon. For these reasons the effectiveness
and required precision of the naval blockade or embargo in
achieving the desired endstate is questioned in both the
planning phase and, with increased vigor, months after being
placed in position. Answers to these questions are elusive
and are yet to be decided for the naval blockades the United
States participated in during the Reagan, Bush, and now
Clinton administrations. There are many factors a blockading
force must consider and which, when applied, contribute to the
success of the blockade. Several of these key factors will be
used in analyzing the apparently successful naval blockade
placed against Iraq compared to the questionable success of
the Haitian blockade. In conclusion several intrinsic factors
contributing to the questionable effectiveness of blockades
Economic pressure may be brought to bear on a belligerent
in degrees, ranging from restricting specific commodities as
with an embargo or sanctions to full fledged air and sea
blockade of all trade.
"An embargo is generally an order by a government to
forbid ships to enter or leave its ports and is issued with
the intent of imposing legal restriction, hindrance or
restraint on commerce." 1 An embargo involves domestic
prohibition of trade, total or specific, with a belligerent
country. Most often an embargo is placed on arms, munitions,
and materials of war.
An embargo does not necessarily include naval or air
power for enforcement, but a show of naval force may be
required to ensure observance. An embargo may simply rely
upon collective monitoring of shipping manifests to track
prohibited cargoes. Detention in port, with confiscation of
vessels and cargo found to be in violation of the embargo is
legal under international law.
A blockade can be considered an act of war or an act
short of war and comes in different forms. It can be
offensive or defensive, near (tactical) or distant
An offensive blockade is directed toward physically
denying the movement of commodities to or from the belligerent
nation. The offensive blockade provides strategic leverage
for negotiation of disputes by inflicting hardship and
inconvenience which weaken the belligerent resolve and works
in partnership with a military offensive by cutting off the
supply of materials and revenue necessary for continued
conduct of war. The naval blockade imposed against Iraq by
the United Nations following Iraq's invasion of Kuwait on 02
August l990 is an example of an offensive blockade.
The defensive blockade is a protective measure
established in order to prevent the movement of unwanted
commodities, contraband, or enemy personnel into that nation's
territory or to prevent enemy warships from going to sea where
they would present a threat to friendly shipping. The
introduction of air and naval forces in the "War on Drugs,"
though not sufficient in numbers to be totally effective, is
an attempt to form a defensive blockade to prevent the flow of
illegal drugs into the United States.
The near blockade, off the coast or outside the port of
the enemy was popular when weapons were limited in range and
the only threat was coastal artillery. In the near blockade
enemy activity could be monitored full time. With the advent
of mines, torpedoes, and missiles the use of the near blockade
became too dangerous and costly to use.
The distant blockade, established farther beyond the
enemy's coast, became the method of choice by necessity.
Today, new technologies such as radar and radio communications
make distant blockades nearly as effective as near blockades
The term "sanction" covers , in a broad sense, those
devices that are used to enforce or induce adherence to
international law and the laws of war.2 As such the naval
blockade and the embargo are both devices which fall under the
category of sanction.
Only because it is often misused one final term deserving
of clarification is quarantine. This term is often wrongly
used to identify a forceful means of trade warfare similar to
blockade. The label quarantine is used with the intent of
identifying a belligerent action with a non-belligerent label,
for example President Kennedy's Cuban Quarantine.
Used correctly, quarantine is the practice of restricting
the movement of passengers and cargo into a country to prevent
the introduction of animal and plant diseases. Quarantines
are enforced in port by inspectors who review manifests and
inspect cargo searching for banned or infected plant and
animal products. Any items found in violation can be seized
for destruction or turned away. Establishing and maintaining
a naval blockade requires significant naval power and long
term dedication. Public opinion, both nationally and
internationally, is required if a blockading nation is to
successfully implement and maintain a blockade. The burden of
unilateral enforcement was removed from the United States
early in the case of Iraq versus the international community.
Internationally reaction to Iraqi invasion of Kuwait on August
02, l990 was swift. The United Nations, on the day of the
invasion, passed Resolution 660 by unanimous vote demanding
Iraq withdraw immediately from Kuwait. Various nations took
independent action freezing Iraqi and Kuwaiti assets, halting
arms shipments, and imposing a boycott of oil imports from
both Iraq and Kuwait.
On August 06, l990 the U.N. Security
Council, acting under Chapter VII of the
U.N.Charter, voted l3-0 (Cuba and Yemen
abstaining) to require all member states
to prevent the import of "all commodities
and products originating in Iraq or
Kuwait exported therefrom after the date
of the present resolution. "(Resolution
66l) The Resolution also prohibited any
transfer of funds to Iraq or Kuwait, and
prohibited the sale or supply of any
commodities or products (excluding
medical supplies and, in humanitarian
circumstances, foodstuffs) to Iraq or
Actual enforcement of UN Resolution 661 with ships from
l3 nations began on August l7, l990, with an interception in
the Red Sea by the USS John L. Hall (FFG 32) of the Iraqi oil
tanker Al Fao. Maritime Interception Operations continue to
this day in support of UN Resolutions against Iraq with a
weakening of determination appearing among various countries.
France and Russia are pressuring to ease the blockade and
allow trade to resume with Iraq while the United States,
sympathetic toward a nation considered important to the
Mideast peace process, has quietly ignored recent Jordanian
violations of the blockade.
In the case of Haiti neither national or international
support came willingly. President Jean-Bertrand Aristide was
overthrown by a military coup in August l99l. The United
States promptly backed the Organization of American States
call for an economic embargo by initiating weak bilateral
trade sanctions against Haiti which were not strictly
enforced. Contradictory signals from both the Bush and
Clinton administrations contributed to the hesitancy of the
international community in responding to the situation.
With rare exception the economic blockade against Iraq
has been effective in isolating Iraq from international trade,
reaching nearly 100 percent effectiveness during the Gulf War.
Continuation of this success is possible only through near
total control of the land, sea and air routes which blockade
runners must use. The main effort against Iraq takes place in
the North Red Sea targetted against ships bound for Aqaba,
Jordan, which shares a land border with Iraq. Leaks to the
embargo occur primarily through smuggling across this border
between Jordan and Iraq. Despite violations receiving high
level attention, with pressure being applied on Jordan to
support the blockade, the violations continue allowing Iraq to
rebuild its defensive and offensive capabilities.
The chokepoint between the Red Sea and the Gulf of Aqaba,
as well as deep navigable water, are factors which benefit the
interception ships. Interception ships are able to closely
monitor and block the chokepoint and the deep water allows
pursuit of shallow draft blockade runners. Any vessel stating
her destination as Aqaba is boarded and searched to ensure
that no cargo is manifested for delivery to Iraq.
Enforcement of the U.N. embargo against Haiti was not as
vigorously pursued as the embargo against Iraq. The primary
reason for this being lack of national support in the U.S.
which was the predominant naval force available for
In dramatic contrast to the strict
enforcement of sanctions against Iraq, in
which U.S. naval vessels aggressively
intercepted and boarded ships, three oil
tankers reportedly managed to slip into
Haiti, providing fuel to keep the
military machine going. Haitian
parliamentarians also complained to the
U.S. Congress that a steady flow of
supply planes were landing at Port-au-
Prince airport each night. . .The United
States quickly abandoned the pretense,
announcing on February 4 that the embargo
would be relaxed for U.S. companies
running assembly plants that employ cheap
labor in Haiti.4
Added to the apparent policy weakness which hampered
warships in stopping these large blockade running ships the
jagged coast line with its restricted waters in which the
large warships were unable to maneuver benefitted the blockade
runners with smaller, shallow draft vessels.
That leaves the jagged shoreline to
"coast- huggers," wildcat fuel runners
who use the cover of darkness to spirit
drums of gas and diesel into Haiti's
biggest harbors. Together with small
tankers operating out of Venezuela
and Panama, which do not observe the
embargo, the armada of smugglers have
managed to deliver so much contraband
fuel that hustlers have set up a bustling
business along "gasoline alley" in Port
Not only did the air and naval enforcement of the embargo
prove ineffective but strong trade across the border with the
Dominican Republic continued with an estimated 10,000 Haitians
daily crossing to buy fuel to be sold on the black market.
The ineffectiveness of the blockade was significant in that
the Haitian leadership continued to function despite the
sanctions and was further emboldened in its defiance of the
As seen in Haiti, a naval blockade by itself is usually
ineffective in obtaining the desired results. The successful
naval blockade relies heavily upon operations being
simultaneously conducted ashore. These operations may include
actual invasion by ground forces, an aerial bombing campaign,
or simply the believable threat of such invasion or attack.
The show of force demonstrated by the introduction of
U.S. forces into Saudi Arabia on l4 August l990 and the
blockade which began on l7 August l990 failed to impress
Saddam Hussein. He obviously felt time was on his side and
expected a weakening of wills with gradual acquiescence from
the world community over the Iraqi seizure of Kuwait. Through
economic sanctions the international body hoped to convince
Iraq to withdraw from Kuwait. In order to maintain the non
violent posturing, President Bush, though prepared to use the
U.S. Navy to enforce these sanctions, avoided describing the
sanctions as a blockade. Saddam Hussein rejected United
Nations ultimatums to withdraw from Kuwait and the offensive
to drive Iraqi forces out of Kuwait began on January l7, l99l.
Military leaders in Haiti were confident that the U.S.
would not resort to military force for several reasons.
First, the U.S., U.N., O.A.S. and even President Aristide were
initially outspoken against the introduction of military
forces. Secondly, repeated American threats and associated
deadlines passed without enforcement. Finally, emboldened by
their success in turning away the USS Harlan County, carrying
American and Canadian military trainers as part of the
Governors Island Accord, the Haitian military felt they could
prolong the political conflict without any real threat from
the United States. It was not until notification that U.S.
Forces were enroute to forcefully remove them from power and
reinstall the legitimate government in Haiti that agreement
for a peaceful settlement was reached.
The greater a nations dependency upon sea trade the
greater its vulnerability to coercion by naval blockade. Iraq
depends upon sealift for export of its primary source of
revenue, oil (30 million dollars per day), and for the import
of the majority of its supplies, both military and domestic.
The blockade resulted in ". . .Iraq los[ing] 90 percent of its
imports, 100 percent of its exports, and had its gross
national product cut in half."6 reduction of spare parts
and equipment as well as beans, oil, and bullets brought
Saddam's once mighty war machine to the brink of collapse.
An island nation the size of Maryland, Haiti is primarily
an agrarian society, with 75 percent of the population relying
upon small scale subsistence farming. Approximately 75
percent of the population live in abject poverty with little
to export and no money for significant imports. Haitians
relied mostly upon sea transport to deliver humanitarian
supplies and these were exempted from the embargo. Aside from
demonstrating U.N. disapproval for the Haitian regime the
economic blockade against impoverished Haiti had little merit.
What do the blockades against Iraq and Haiti have in
common? There are several intrinsic features of a blockade
which must be evaluated by the blockading nation. These
features contribute to targetting inaccuracies and complicate
measurement of blockade effectiveness.
There is little question that the blockade imposed
against Iraq was successful in weakening the Iraqi military
both materially and psychologically, contributing greatly to
the shaping of the battlefield. Four years after the Gulf War
and without the threat of military intervention to support it,
the blockade has failed to achieve all the intended goals. On
the other hand, no evidence can be found to indicate the
blockade imposed against Haiti contributed in any measurable
way to restoring the democratically elected president to
The length of time required for the blockades to pressure
both Iraq and Haiti to comply with the dictates of the
international community has not been determined. Iraq
continues to defy the world despite continuance of the
blockade, and Saddam Hussein remains firmly in power. Iraq
has proven capable of rebuilding its military and repairing
most wartime damage even with a blockade in place. The
question that needs addressing is how long should the blockade
remain in place even when its usefulness in achieving the
desired endstate becomes questionable.
This pressure on Iraq, this barbarian
policy of starving a whole population
to force them into rebellion against
the regime, has the contrary effect
because it increases the dependence of
the people on this government.
Political change is too luxurious a
thought to indulge in if you are busy
The military leadership in Haiti would probably never
have ceded control of the government because of hardships
brought about by the naval blockade alone. How long could the
United States expect the international community to support an
unpopular blockade? Repressive regimes must have something
personal to loose (or gain as in the case of Haiti) before
they willingly surrender control of a nation. It was not until
the introduction of military forces to physically remove them
was initiated did the regime in Haiti finally capitulate.
Western nations tend to evaluate blockades based upon
economic damage and hardship. Iraq and Haiti, being Third
World nations, do not provide their citizens with a standard
of living equivalent to even the poorest of Western nations.
The general population is familiar with subsistence living and
is unfamiliar with luxuries Westerners depend upon in their
daily lives. The impact of a blockade is slow in developing
even in industrial countries. The impact on Third World,
under-developed nations is significantly less and may be of
Neither Saddam Hussein of Iraq nor the military
leadership in Haiti were particularly concerned with the
welfare of the populace. The hardships endured by the general
population were not shared equally by the leadership or the
military, the designated targets of the blockade. Both the
leadership and the military received priority in food, fuel,
medicine in order to maintain their control of the countries.
In the case of Iraq, ". . . the United States provided evidence
that President Saddam Hussein was spending lavishly on his own
comforts while millions of Iraqis lacked food and medicine.
... the Iraqi leader has spent more than $500 million on dozens
of opulent new palaces for the exclusive use of his family." 8
The target of the blockade, those in power, control who has
money and food. The Iraqi government lives virtually
unaffected by the blockade while the common Iraqi citizen
lives in poverty, forced to sell family possessions to
purchase basic necessities.
In Haiti the leadership and elite actually benefitted
from the blockade.
The handful of wealthy families who
directly or indirectly support the
junta maintain their near monopolies
on items exempted from the blockade,
such as cooking oil, rice, and sugar--
and are profiting handsomely. . .black
marketeers slapped an $11 charge on
every case of supplies. Canned milk,
a substitute for nonexistent fresh milk,
has doubled in price. The poor people
can't afford it. . .Everything is for the
rich first. 9
Stories of hardship and death were used as political
weapons by the leaders in both Iraq and Haiti. "In fact, the
military is counting on headlines about rising malnutrition
and disease to weaken the international community's resolve."10
A naval blockade is a two edged-sword, injurious to
combatants and non-combatants alike. The simple act of
declaring an economic blockade has significant impact on
shippers to that area of the world and to other countries.
In the Red Sea boardings did not take place after sunset as a
safety issue. Any merchant that could not be boarded and
inspected prior to sunset was not allowed to proceed and was
required to lay to until the next morning. The cost of the
delay runs into the tens of thousands of dollars a shipper
loses in operational costs while sitting at anchor unable to
deliver the cargo. Further, there is an increased danger of
sailing into what may be considered a war zone and the
possibility of increased insurance premiums. The incentive to
conduct shipping within the blockade area is greatly reduced
and many shippers are financially forced to avoid the area of
Again using the North Red Sea interdiction effort as an
example, trade to Jordan and Israel were significantly reduced
by the naval blockade against Iraq. Indeed, "...financial
losses [were] incurred by Jordan as a result of delays caused
by a US--led Naval force...Jordanian losses are estimated at
more than 1.4 billion since the sanctions were applied against
Iraq in August 1990."11 Other nations, Russia, France, China,
and Turkey were also big trading partners with Iraq and would
like to see an end to the blockade and resumption of trade
This reduction in shipping also has an impact on the non-
combatants within belligerent country. Even though food
and medicine may be exempted from the embargo, the reduced
shipping in general reduces available foodstuffs and medicine
into the blockaded country.
In both Haiti and Iraq, the blockades impacted the lives
of the non-combatants more than the intended targets. This is
an unavoidable occurence with the economic blockade. The
question that must be answered in the planning stages must be
whether set goals are achievable and whether the suffering
inflicted upon unintended victims is justified by the results.
In the case of Iraq the initial results, cutting off war
materials to Hussein, appear to support the blockade.
Continuation of the blockade alone to pressure Iraq to abide
by remaining United Nations Resolutions is questionable.
In the case of Haiti, the poorest country in the Americas
with a small and ill equipped military, the naval blockade
succeeded only in demonstrating the international communities
opposition to the Haitian regime. The aim of pressuring the
regime to surrender power was not achievable through economic
For an economic blockade to be effective each case must
be viewed individually, taking into consideration the aim to
be achieved and the situation both politically and
economically for that specific nation. The questions that
bear answering are will the blockade impact its target and is
the collateral damage to the civilian population acceptable?
1. Naval Warfare Publication 10, Warfare Naval
Warfare College, Newport, RI. 03 March l972, p 2-9.
2. Naval Warfare Publication 10.
3. CDR Jane Gilliland Dalton, JAGC, "The Influence of
Law on Seapower in Desert Shield/Desert Storm," Naval Law
Review Vol 41, l993, p 30.
4. John Canham-Clyne, "Haiti After the Coup," World
Policy Journal Fall l994, p 350.
5. Kevin Fedarko, "To Have and To Have Not," 06
June l994, p 32.
6. General Norman Schwarzkopf, "A Tribute to the Navy-
Marine Corps Team", August l99l, p 44.
7. Youssef M Ibrahim, "Baghdad's Burden", The New York
Times 25 October l994, p Al.
8. Richard D. Lyons, "U.N Council Decides to Keep
Economic Sanctions on Iraq", New York Times 15 November
l994, p A6.
9. Fedarko, p 32.
10. Fedarko, p 33.
11. Lamis Andoni, "US Lifts Red Sea Blockade In Peace
Gesture to Jordan", Christian Science Monitor 27 April l994,
1. Andoni, Lamis. "US Lifts Red Sea Blockade In Peace Gesture
to Jordan". Christian Science Monitor, 27 April l994 ,p 3.
2. Canham-Clyne, John. "Haiti After the Coup". World Policy
Journal FALL l994, pgs 348-364. An interview with Haitian
ambassador to the United States, Jean Casimir.
3. Gilliland Dalton, CDR, JAGC. "The Influence of Law on
Seapower in Desert Shield/Desert Storm". Naval Law Review Vol
4l, l993, pgs 27-82.
4. Fedarko, Kevin. "To Have and To Have Not." Time 06 June
l994, pgs 32-33.
5. Ibrahim, Youssef. "Baghdad's Burden." The New York
Times, 25 October l994, pgs A1 - A12.
6. Lyons, Richard. "U.N. Council Decides to Keep Economic
Sanctions on Iraq." The New York Times, l5 November l994, p
7. Naval Warfare Publication 10, Naval Warfare. Naval War
College, Newport, RI, 03 March l972, pg 2-9
8. Schwarzkopf, Norman, GEN. "A Tribute to the Navy-Marine
Corps Team." Proceedings, August l99l, 44. Speech presented
to the Naval Academy Class of l99l.
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