Several nations are challenging decades of effort by the international community to prevent the spread of nuclear weapons. Robert D. Blackwill and Albert Carnesale, along with eight other experts, analyze the national security consequences for the United States if new nuclear-weapon states emerge to threaten American interests. The contributors examine the nations most likely to cross the nuclear threshold and how these countries would acquire, maintain, and protect their new nuclear weapons capabilities. Individual chapters address: how nuclear weapons in Saddam Husseins hands could have altered the outcome of the Gulf War; the ways that American diplomacy and international arms control could meet the dangers posed by new nuclear nations; U.S. military options for dealing with the nuclear weapons and delivery systems of new proliferators; the role and limitations of intelligence systems of new proliferators; the role and limitations of intelligence in penetrating hostile nuclear programs; and the circumstancesif andunder which the United States should provide technical assistance to increase the safety of emerging nuclear arsenals.