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Should We Attack Iran to Halt its Perceived Nuclear Weapons Programme?

Commentary, 17 November 2010
Middle East and North Africa
Advocates of pre-emptive attacks on Iranian nuclear related facilities and/or regime change should recognise that the risks and costs of such an attack remain prohibitive.

Advocates of pre-emptive attacks on Iranian nuclear related facilities and/or regime change should recognise that the risks and costs of such an attack remain prohibitive.

By Kenneth Freeman for


Iran flagConcerns about the actual status of Iran's perceived intentions to acquire nuclear weapons - coupled with concerns in some quarters that significant segments of the Israeli population are suffering from 'existential angst' that needs to be assuaged - has led to calls that either Israel attack and destroy the purported Iranian facilities or that the US and its allies do so. Some advocates, such as US Senator Lindsey Graham, desire regime change. Senator Graham reportedly said, at the recent Halifax conference, that 'any military strike on Iran to stop its nuclear program must also strive to take out Iran's military capability...the U.S. should consider sinking the Iranian navy, destroying its air force and delivering a decisive blow to the Revolutionary Guard...they should neuter the regime, destroy its ability to fight back and hope Iranians will take a chance to take back their government.'[1]

President G.W. Bush acknowledges in his memoirs that the balance of evidence, risk, effectiveness and cost led him to reject in 2007 proposals to attack Iran's nuclear facilities.[2] Interested parties, if able to come to an agreement on a course of action, could choose to continue to rely on diplomacy, sanctions, containment and deterrence to hinder any Iranian ambitions to develop and deploy nuclear weapons and dissuade their use if deployed. This approach continues to be employed with North Korea.

Additional sanctions to ensure Iranian compliance with its obligations under the Nuclear Non-Proliferation Treaty (NPT) can be imposed. For example, with UN authorisation, it would be a relatively simple task to destroy the cracking towers in the nine existing Iranian refineries. These are estimated to provide about two thirds of gasoline consumption and 90 per cent of diesel consumption.[3] Attacking four refineries would eliminate about 75 per cent of capacity (Abadan, Isfahan, Tehran and Bandar Abbas).[4] The economic impact might undermine support for the current regime. 

Uncertainty and Complexity

There is significant uncertainty regarding the size and scope of Iranian activities in the relatively detectable arena of enrichment, and ambiguity as to the size, nature and intentions of Iranian nuclear weapons related research. Many of the known facilities have been dispersed, often in underground hardened facilities that may be more difficult to destroy than many perceive. Even advocates of such attacks often acknowledge that they are unlikely to set back a serious Iranian nuclear weapons programme by more than one or two years.

Advocates of a pre-emptive attack on Iran's nuclear related facilities and military forces should consider the international political and economic consequences, the actual forces required to do so, and the size, cost and duration of a successful occupation of Iran.

The current government, despite recent large-scale protests, still appears to enjoy support in a significant proportion of the population, and in such favoured sectors as the Revolutionary Guard and the Basij, a paramilitary group. As in Iraq, these are likely to become centres of resistance even after complete military defeat and occupation. Advocates of intervention might also reflect that at the time Iraq launched its attack on Iran in 1980, the, then new, Iranian regime's hold on power was tenuous. But once attacked, the population rallied behind the Iranian government and endured heavy casualties during the eight year war. Western support of Iraq during the conflict is unlikely to be forgotten, raising the risk that a military intervention will not be viewed with equanimity by all sectors of Iranian society.

The continuing problems in Iraq and Afghanistan demonstrate the consequences of not understanding what is required for a successful occupation and preparing for it prior to the initiation of hostilities. Advocates of military action, political decision makers, and military leaders and planners should be mindful of the opportunities for Iran to create difficulties before, during and after build-up and initiation of hostilities. A wide variety of Iranian actions could be troublesome in Iraq, Afghanistan, Lebanon, the Gulf States and the Palestinian territories as would efforts to obstruct international shipping and air traffic. Nor can activities further afield be ruled out.

Finally, advocates should be aware that countries in which the people attempt to 'take back the government' during a period of hostilities with the outside world have a regrettable tendency to degenerate into sustained civil war, requiring occupation forces to restore and maintain order for significant periods of time (decades). As in Iraq and Afghanistan, the diversity of ethnic and religious groups in Iran does not bode well for a peaceful transition under fire. (See Figure 1)

Ethnic Groups in Iran

Figure 1: The population of Iran is estimated by the CIA World Fact Book to be 77 million with the median age of 26 and 73 per cent, over 50 million, in the age 15 to 64 (the most useful age groups for recruiting organised forces and sustaining resistance activities).

What Would It Take To Successfully Occupy Iran?

A military intervention may lead to the need to invade and occupy Iran even if this was not originally intended. This could be due to an escalation of the conflict or the emergence of a more dangerous regime as a result of the initial actions. Alternatively, Iran might fissure on its fault lines in the manner of Iraq and the former Yugoslavia if the population heeds Senator Graham's call for them to 'take back their government'. 

Recent experience in Iraq, Afghanistan and the Balkans show, even if the defeat of the organised military forces can be achieved quickly and cheaply, the annual cost, risks and duration of such an occupation may be greater than the advocates of military intervention expect.

Experience indicates that the forces required to conduct a successful relatively simple occupation are on the order of 20 peacekeepers/occupation troops per thousand population.[5] (See Figure 2) This would indicate that a successful occupation of Iran would require the deployment of at least 1.5 million troops and could last for decades. Numbers could increase when adjusted for difficulties such as terrain and communal tensions. Occupation requirements are unlikely to be appreciably less if the country unravelled under attacks that did not include the use of ground troops. The size, duration and cost of an occupation can be expected to increase if an active opposition is supported by neighbouring countries.

A reasonable troop rotation is typically about one year deployment in three. The sustained deployment of 1.5 million troops for this contingency alone would require total forces of about 4.5 million. It costs the US about $1 billion per year per thousand troops deployed in Iraq or Afghanistan. Costs could be reduced by, for example, conscription and a more frugal approach to equipping and operating the occupation forces. But, even if this reduced costs by a factor of five, the expected cost of such an occupation would be several hundred billion dollars per year.

Both an attack on Iran and any subsequent occupation could cause economic turmoil.  This would limit the ability of a country participating in the attack to pay for their costs and/or subsidise other participants in a 'coalition of the willing'.

Troop Ratio Interventions

Figure 2: See Burden of Victory: The Painful Arithmetic of Stability Operations by James T. Quinlivan, available online at:

Is it Prudent to Leave it to Israel?

Some advocates of intervention, feel that the task can be unilaterally entrusted to Israel. This may prove a doubtful proposition, even if the initial intervention only intended to use the Israeli Air Force (IAF) to attack the known nuclear related facilities. As discussed, such attacks are unlikely to delay a true nuclear weapons programme by more than a few years. They run the risk of helping the current regime consolidate and maintain its power. Senator Graham's call to destroy the forces supporting the regime in order to lead to its collapse - even if it were to prove possible to conduct solely with air power - run the risk of causing the country to split along its fault lines. The resulting chaos might require the deployment of ground forces to impose order to prevent genocide and/or ensure oil production continued.

In this circumstance, it is unlikely that the Israeli Defense Force (IDF) could provide sufficient forces even if we discount a) the logistical difficulties of bringing and sustaining IDF ground forces in Iran and, b) the probable popular reaction on the part of both Iranians and the wider Middle East, who might find intervention and occupation by the IDF to be distasteful.  

Israel's ability to quickly generate enormous combat power rests on a relatively small full-time military, together with a draft and reserve forces that requires a very high proportion of military aged people to participate, and large numbers of highly trained reserves. Large scale deployments of reserve forces for extended periods of time are costly to the economy. The deployment of 1.5 million occupation troops would represent roughly 21 per cent of Israel's total population. The resulting costs would far exceed Israel's (GDP about $200 billion) ability to sustain economically.

In the unlikely event that the Israelis were willing to provide the required forces on their own, they would require massive financial support from the outside. At best, such subsidies are likely to prove politically unpalatable in countries such as the US and EU member states at a time of severe budgetary stringency.


In the past, policy makers considering pre-emptive attacks on sovereign nations to prevent them developing and deploying nuclear weapons have concluded that a policy consisting of dissuasion, containment, deterrence, sanctions and diplomacy was preferable. This was based on careful analysis that concluded it was the more cost effective, lower risk, and morally superior option.  

For all of their faults, sanctions and the inspection regimes utilised after the First Gulf War did succeed in preventing Iraq from developing and deploying nuclear weapons and led to its abandonment of other weapons of mass destruction. The subsequent invasion - by forces clearly inadequate for a successful occupation - has, to date, despite enormous costs, not achieved the objective of installing a democratic friendly regime with wide spread popular support and legitimacy. Nor is regime change in Iran through military intervention likely to be easy. 'Existential angst', wishful thinking and carefree disregard of costs and risks should not drive policy.

Dr. Freeman has been an Associate Fellow at RUSI, taught Force Planning and Analysis at the US Naval War College, a Visiting Scholar at CIS, MIT, and a Senior Analyst at the US Congressional Office of Technology Assessment.  He is currently Vice President New Hill Management LLC.

*The views expressed in this article are not the views of the Royal United Services Institute, but are the views of the author*


[1] 'Senator: consider taking out Iran's military' The Associated Press, November 6, 2010; 4:48 PM - (Available at:

[2] Agence France-Presse, 'Bush sought military options on Iran' 10 November 2010,, accessed 10 November 2010

[3] US DOE Energy Information Association, 'Iran Oil',, accessed 15 November 2010

[4] Iran refinery capacity can be found at 'List of Oil Refineries' on Wikipedia at:

[5] James, T., Quinlivan, 'Force Requirements in Stability Operations,' Parameters, Winter 1995, pp. 59-6


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