"Following U.S. unilateral abrogation of the ABM Treaty, the prospect of yet another round of the multilateral and destabilizing nuclear arms race now stares humanity directly in the face. The entire edifice of international agreements regulating, reducing, and eliminating weapons of mass extermination has been shaken to its very core. The Pentagon's new "Nuclear Posture Review" outlines an array of political, strategic and tactical scenarios under which the U.S. government might now resort to nuclear arms, transforming nuclear weapons use from "the unthinkable" to a policy option - and shaking the very foundations of the Nuclear Non-Proliferation Treaty Regime. As its War on Terrorism hurtles into uncharted waters, challenging accepted norms of international law and setting a pattern for peremptory state behavior, could the U.S. cross the nuclear threshold?"--BOOK JACKET.