U.S. Arms Sales Policy

December 4, 2019 • Publications

Arms sales can play an important role in American foreign policy, but there are significant risks in sending billions of dollars of deadly weapons abroad, including blowback (wherein American weapons end up being used against American interests) and dispersion (in which weapons sold to a foreign government end up in the hands of criminal groups or adversaries). U.S. arms sales policy should prioritize transparency, data collection, and risk mitigation.

Policy Recommendations

  • Develop methodology to determine risk profiles of potential buyers. Such profiles would enable policymakers to determine which nations should receive American weapons.
  • Suspend arms sales to risky nations. The United States should stop sending weapons to countries where the risk of serious negative consequences is high.
  • Track the use of American weapons. The United States should expand its end‐​use monitoring of weapons to ensure responsible use and to inform future arms sales decisions.
  • Require congressional approval. Congress should approve all major arms deals and revoke the president’s ability to sell arms through emergency powers.
  • Increase transparency. Congress should increase the transparency surrounding the assessment and approval processes to better inform public debate.


The United States has long been the world’s leading arms exporter. In 2018, the Trump administration notified Congress of $78 billion in major conventional weapons sales, giving America 31 percent of the global arms market. Between 2002 and 2018 the United States sold at least $560 billion of major conventional weapons to 168 different nations.

Unfortunately, there are numerous examples of arms sales harming U.S. national interests. Over the past decade alone U.S. weapons have wound up in the hands of the Islamic State, have landed on the black market in Yemen and elsewhere, and have been used by oppressive governments to kill their own people. More broadly, American arms sales have helped prop up authoritarian regimes, encouraged military adventurism, spurred arms races, and amplified existing conflicts.

The negative consequences of arms sales are not new. After the Iranian Revolution in 1979, the revolutionary government took possession of billions of dollars’ worth of American fighter jets and other weapons, an arsenal that Iran is still using. In 1993, American troops ended up fighting other forces in Somalia that were armed with American‐​made weapons, a story that has repeated itself throughout the war in Afghanistan.

Currently no historical data exists to adequately measure how often these various outcomes occur or under what circumstances they are more or less likely. Policymakers should require the collection of such data. They should also fix the risk‐​assessment process required by the Arms Export Control Act of 1976, which recent history strongly suggests is broken. Collecting data and improving the processes that govern arms trade policy would allow policymakers to confidently use this tool to enhance U.S. security while also mitigating the risks.

Additional Resources

“The 2019 Arms Sales Risk Index” by Trevor Thrall, Caroline Dorminey, and Jordan Cohen, Cato Institute, September 10, 2019.

Trends in Major Arms Sales in 2018: Fact Sheet by William Hartung and Christina Arabia, Center for International Policy, April 17, 2019.

“Arms Bizarre: Selling Weapons in the Age of Trump” by Emma Ashford and Trevor Thrall, featuring Caroline Dorminey, Power Problems, podcast, April 16, 2018.

“Risky Business: The Role of Arms Sales in U.S. Foreign Policy” by Trevor Thrall and Caroline Dorminey, Cato Institute Policy Analysis no. 836, March 13, 2018.

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