The Long Shadow is the first comprehensive, systematic examination of the roles and implications of nuclear weapons in the dramatically different post–Cold War security environment. Leading experts investigate the roles and salience of nuclear weapons in the national security strategies of twelve countries and the ASEAN states, and their implications for security and stability in a broadly defined Asian security region that includes the Middle East. The study also investigates the prospects for nuclear terrorism in Asia.

A chief conclusion of the study is that nuclear weapons influence national security strategies in fundamental ways and that deterrence continues to be the dominant role and strategy for the employment of nuclear weapons. Offensive and defensive strategies may increase in salience but will not surpass the deterrence function. Another major conclusion is that although there could be destabilizing situations, on balance, nuclear weapons have reinforced security and stability in the Asian security region by assuaging national security concerns, strengthening deterrence and the status quo, and preventing the outbreak and escalation of major hostilities.

As nuclear weapons will persist and cast a long shadow on security in Asia and the world, it is important to reexamine and redefine "old" ideas, concepts, and strategies as well as develop "new" ones relevant to the contemporary era. In line with this, the global nuclear order should be constructed anew based on present realities.