The most likely setting for the world's first nuclear war, observers generally agree, is South Asia, where India and Pakistan harbor small, undeclared nuclear arsenals and deep, often-declared mutual animosity. Chartered to determine whether and how the tense stability that now marks India-Pakistan relations might break down, this project identifies several paths to conventional and perhaps nuclear war. Neither country's view of nuclear weapons and warfare seems likely to produce the deterrent stability that marked the mature superpower relationship of the Cold War; rather, each sees some value in brandishing nuclear weapons in ways that could contribute to instability in a crisis. Nor are crises difficult to envision. In the near- to mid-term, the unconventional conflict that now simmers around Kashmir will continue, and could unexpectedly escalate to major conventional war. In the longer run, growing relative economic and military power could tempt India to launch a premeditated attack on Pakistan, should the latter not reach an accommodation with India before then. The study found that India and Pakistan both assume that outside powers, mainly the United States, will intervene to stop any major war on the subcontinent within two weeks after it begins. Should one of them launch a war on the basis of that assumption only to discover that it is incorrect, misperceptions of U.S. policy will have contributed to instability and raised the possibility of nuclear use as the war proceeds.