SSN Key Findings

Is Military Aid an Effective Tool for U.S. Foreign Policy?

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University of North Carolina at Chapel Hill

The United States spends billions of dollars every year on military aid to foreign governments around the world, in the hope that aid will boost national security and increase American influence. Since the 9/11 terrorist attacks, military assistance has increased and gone to more countries. In the fight against terrorism, U.S. authorities have sent military aid to Armenia, Azerbaijan, Tajikistan, Pakistan, Ethiopia, Nigeria, Oman, Yemen, Uzbekistan, and Columbia, among other nations.

Does giving military aid work? Sometimes, the benefits are clear. After America enormously increased aid to (the former Soviet republic of) Georgia, that country sent 2,000 soldiers to support the U.S. war effort in Iraq. But at other times, the United States gives aid without gaining new leverage. Pakistan, for example, is widely believed to have channeled a portion of billions in U.S. military aid dollars to extremist groups, and Pakistan’s military retains ties to the very same Haqqani network and Taliban militants who are killing U.S. soldiers fighting in Afghanistan.

Can Military Aid Buy Cooperation?

Scholars offer competing theories about the impact of military aid:

  • Arms for Influence. This theory predicts that a foreign government’s level of cooperation will grow as U.S. military aid increases. Accordingly, U.S. authorities should continue military aid to cooperative countries and reduce or eliminate aid when governments fail to support American foreign policy positions. 
  • The Lonely Superpower theory posits that dependence on a powerful state can fuel defiance. Governments receiving significant amounts of military aid may temper their cooperation with the United States, or even openly defy our leaders, in an attempt to avoid being viewed as “American puppets” by domestic and international audiences.
  • The Reverse Leverage model suggests that, paradoxically, a powerful nation can become dependent on countries it aids. In this way of thinking, the amount of military aid granted to a foreign government reflects the extent to which the U.S. is reliant on that nation – for things like oil exports, intelligence, bases for troops, and military cooperation. In this perspective, it could be easier for a nation receiving assistance to obtain military aid elsewhere than for a superpower like the United States to find an equally valuable strategic partner. Rather than inducing compliance, generous U.S. military funding runs the risk of creating strong clients who are able to ignore U.S. interests and play us off against other powers.

What the Evidence Shows

The world is much more complicated than any one model can capture. Each nation receiving major military aid has a unique relationship with the United States that changes over time. Nevertheless, a thorough investigation of the connections between U.S. military aid and the level of foreign policy cooperation exhibited by the governments that received aid between 1990 and 2004 reveals a pattern largely consistent with the Reverse Leverage model.

  • In general, U.S. military aid proved to be negatively correlated with cooperation by the nations receiving the aid. In fact, national governments that received aid exhibited less cooperative behavior toward the United States than governments given no military aid.
  • Some countries that received U.S. military aid became more cooperative with increased levels of assistance. But aid was less likely to induce cooperation from formal U.S. allies.
  • In practice, the United States did not punish defiance with reductions in aid; nor did it reward greater cooperation with increases in military aid. The opposite pattern prevailed, because higher levels of cooperation from nations we assisted were correlated with decreased military aid in subsequent years, while reductions in cooperative behavior were often followed by increased aid.

Can Military Aid Advance American Foreign Policy Goals?

Given these patterns, U.S. policymakers face a difficult dilemma. Providing military assistance may be the only way to gain influence in key countries – such as Pakistan – located in strategically crucial parts of the world. Even if aid does not have a positive effect on the level of cooperation with the United States overall, the U.S. may still get specific benefits. Policymakers, however, still have to cope with the limited utility of military aid for inspiring cooperation with overall foreign-policy goals. Providing military assistance may at times allow the United States to avoid the costs of direct military interventions, but leaders should take care not to hurt long-term American security interests. U.S. leaders must:

  • Have realistic expectations. Realize that military aid might achieve short-term security goals, but will not usually induce general cooperation.
  • Acknowledge constraints on flexibility. Military aid is not a very effective carrot or stick, because it cannot easily be turned on and off. Immediate U.S. security needs may impel aid, but don’t imagine that flows of aid can be calibrated over time to change a foreign government’s policy preferences. 
  • Be cognizant of the risks. Providing military aid to foreign governments can backfire. Arms transfers to developing countries have been linked to increases in human rights abuses and may impede democratization. Military assistance can enable client states to aggress against their neighbors – which may hurt American interests in the region. Finally, when alliances shift or governments are replaced, America can find itself in combat against an enemy equipped with U.S-made weapons sent at an earlier time. That is what happened in Afghanistan. We gave arms to Afghans and Arabs to fight the Soviets in the 1980s, only to see many of the same fighters turn against us in 9/11 and afterwards.

Read more in Patricia L. Sullivan, Brock F. Tessman, and Xiaojun Li. “US Military Aid and Recipient State Cooperation." Foreign Policy Analysis 7, no. 3 (2011): 275-94.