As the most open society on a shrinking planet, the United States has no reliable defense against smuggled weapons fashioned from black-market materials by a determined state or terrorist group. Avoiding Nuclear Anarchy highlights the fact that the only way to combat the threat is by preventing nuclear leakage in the first place. Its message is both timely and urgent: it outlines the new nuclear danger and details how to reshape U.S. national security policy to deal with these dangers.