Why is the US defense budget so big?    

CIS | Audits of the Conventional Wisdom Series
The Center's series continues with an analysis of the US defense budget—the largest since World War II. Is it a rational response to the threats and the dangers that the United States faces—or not? Benjamin Friedman is a PhD student at the MIT Department of Political Science. He is a member of the Center's Security Studies Program and is a research fellow in defense and homeland security studies at the Cato Institute.

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In the Audit series, MIT's Center for International Studies tours the horizon of the conventional wisdoms that animate U.S. foreign policy, and puts them to the test of data and history. By subjecting particularly well-accepted ideas to close scrutiny, we hope to spark discussion and debate, with a result we can all agree on: better foreign policies that lead to a more peaceful and prosperous world.