level of 2,000 to 2,500 deployed strategic nuclear warheads. Unilateral initiatives since the Cold War began winding down have also reduced very substantially the numbers of deployed nonstrategic warheads, especially on the U.S. side. In addition, nuclear testing has ended, the United States and Russia have agreed not to target their missiles against each other on a day-to-day basis, and production of weapons-grade fissile material has stopped in the United States and is expected to stop soon in Russia.
These actions have unambiguously halted and reversed the bilateral nuclear competition that was the most conspicuous characteristic of the Cold War's military confrontation but, unfortunately, have not sufficiently altered the physical threat that these weapons pose. The reduced forces could still inflict catastrophic damage on the societies they target or could target, and the thousands of nondeployed and nonstrategic nuclear warheads not addressed by the START process and likely to be retained without further agreements will pose substantial risks of breakout, theft, or unauthorized use. In addition, the United States and its NATO allies retain their Cold War "weapons of last resort" doctrine that allows the first use of nuclear weapons if deemed necessary to cope with nonnuclear attacks, and Russia has announced that it is abandoning the Soviet Union's no-first-use pledge in order to adopt a position similar to NATO's.
The basic structure of plans for using nuclear weapons appears largely unchanged from the situation during the Cold War, with both sides apparently continuing to emphasize early and large counterforce strikes and both remaining capable, despite reductions in numbers and alert levels, of rapidly bringing their nuclear forces to full readiness for use. As a result, the dangers of initiation of nuclear war by error (e.g., based on false warning of attack) or by accident (e.g., by a technical failure) remain unacceptably high. (On the Russian side, the dangers of erroneous, accidental, or unauthorized nuclear weapons use may be even higher than during the Cold War because of subsequent deterioration of the military and internal-security infrastructure and of morale.) The continuing competitive assumptions underlying some official discussions of the U.S.-Russian nuclear relationship, when coupled with the postures of the forces and the potential for destabilizing deployments of ballistic missile defenses, pose the risk that the arms control fabric woven during the Cold War and immediately thereafter could unravel.
In addition, continued actions by the United States and Russia to reduce their nuclear arsenals—and to reduce the roles assigned to those arsenals—are needed to help bring the other declared and undeclared nuclear weapons states into the arms reduction process and to strengthen the global nonproliferation regime. The effectiveness of that regime depends on the full support and cooperation of a large number of nonnuclear weapons states in the maintenance of a vigorous International Atomic Energy Agency with the inspection powers and resources to do its job, in the implementation of effective controls on the transfer of sensitive technologies, and in the creation of transparency conditions conductive to building