North Korea's test of a nuclear weapon in 2006 shows that such weapons are within reach of determined regional powers. While U.S. conventional and nuclear forces will continue to have deterrent effects on the leaders of regional adversaries, such as North Korea and Iran, the dynamics of the deterrent balance may be quite different from that to which the United States became accustomed during the Cold War.The weakness of these states at the conventional level, coupled with the high stakes they will have at risk in a conflict with the United States, could lead them to seriously consider brandishing or using nuclear weapons in a conflict. This, in turn, could compel U.S. leaders to temper their military and political objectives in such conflicts. This book examines the reasons behind this important shift in the international security environment and its implications for U.S. strategy and force planning. Read Less