The Limits of Force as an Instrument of Foreign Policy

Despite their vast military and technological power, the United States and many of its allies have been bogged down for nearly 10 years in Afghanistan and Iraq. This failure of the U.S. and its allies to achieve their goals in these two countries raises the question of how effective military force is as an instrument of foreign policy and a means of inducing political change. In addition to the intrinsic value of having a correct assessment of the efficacy of different policy instruments, this question is important because, despite the very limited success of military force as an instrument of policy in Iraq and Afghanistan, many in the policy-making community in the U.S. and Europe still believe in the magical capacity of military force to achieve political goals. If unchallenged, this belief could lead to other costly experiments in the use of force, possibly in Iran, with potentially serious negative consequences.

An important reason for the persistence of the belief in the efficacy of military force as an instrument of policy is the confusion in many minds between power and influence. A state’s power can be measured by combining its different capacities in military, economic, and other terms. Influence is the ability to use this power to make others do what one wants them to do or to behave in ways one wants them to behave. If power cannot be translated into influence, then no matter how vast it is, it is of no great value as an instrument of policy or as a means of producing desired change.

Clearly, a powerful country has greater potential than a weak country to influence other countries and international actors, and a strong military force in the background is an important component of that power. However, even the most powerful country will have difficulty in persuading others to behave as it wants them to if the latter see the demands as excessively unreasonable or, more seriously, as threatening their very existence. Having used all other elements of its power without success, a powerful country can always use military force to advance its objectives. But while force can destroy what exists, both physically and institutionally, it still cannot make the antagonist accept the demands made upon it if it still has the will to resist. Paradoxically, in fact, the use of military force often eliminates the incentives for accepting demands, because after being attacked, the antagonist has little left to lose. Therefore, military force can lose its usefulness as an instrument of persuasion the minute it has been used. Military force is even less effective as a means of changing others’ beliefs and ideas; it may even make them stronger.

The limits of military force become even clearer when the country that has used it tries to build new structures to replace what it has destroyed. Because new structures inevitably mean the fashioning of new power relationships and a new distribution of economic and other privileges, various factions in the target country will begin to compete with one another, often against the wishes of the country that has used force.

This is precisely what the United States is now facing in Afghanistan and Iraq. In both countries, various groups are pursuing their own parochial interests, many of which are at direct variance with the United States’ policy goals. Various Afghan and Iraqi factions’ visions for the future of their countries are totally different from those of the United States.

Moreover, the destruction of an existing structure does not eliminate preexisting fault lines, such as ethnic and religious cleavages and historic grievances. In other words, the idea that using force and eliminating a given structure creates a tabula rasa upon which one can write whatever one desires is a mere chimera. This is particularly true of countries and regions with a heavy historical burden and a diverse population. Both Iraq and Afghanistan validate this contention.

In addition, eliminating a particular government and political structure can have broader implications for the balance of regional power and the character of regional relations. Some countries will feel disadvantaged by the changes and will try to influence events in directions best suited to their interests. Others will try to gain a foothold in the new setup. Further, very often the interests of regional actors differ from those of the country that has used military force, even when some of the regional actors are supposedly allies of the invading power. Once again, Iraq and Afghanistan illustrate this principle in action. Thus, Pakistan, the main U.S. ally in Afghan operations, is pursuing goals at odds with those of the United States, and it has been doing so since the Soviet Union withdrew from Afghanistan in 1989. Likewise, in Iraq, America’s Arab allies, notably Saudi Arabia, are pursuing their own interests and ambitions by supporting Sunni groups, including some that are involved in terrorism.

Another factor that limits the value of military force as an instrument of policy is that its costs can be far out of proportion to its benefits. Again, nearly a decade’s worth of blood and treasure spent in Afghanistan and Iraq supports this proposition.

However, despite all these shortcomings, belief in the magic and transformative power of military force persists, and there is little effort to develop less costly alternatives. Yet alternatives to the use of force could achieve basic U.S. and Western security objectives better and at less material and human cost. They could also contribute to stability in volatile regions and would better advance laudable Western values such as democracy and human rights.

Author: Shireen T. Hunter

Shireen T. Hunter is visiting professor at Georgetown University's School of Foreign Service. Her latest book is Iran's Foreign Policy in the Post-Soviet Era: Resisting the New International Order, Praeger, 2010.