in chapter 7, I discussed the calculations of nonnuclear weapon states (NNWS) that confronted nuclear weapon states (NWS) in crises and wars. Beyond wars and crises, what role, if any, has the tradition of non-use of nuclear weapons played in the calculations of nonnuclear states in their bargaining with nuclear states on the conclusion and the renewal of the Nuclear Nonproliferation Treaty (NPT) and associated instruments of the nonprohferation regime? Although it is rarely stated explicitly, it seems the tradition has had an impact on the calculations of a large number of nonnuclear states with respect to their willingness to accede and continuously adhere to the nuclear nonprohferation regime. I argue that the presence of the quasi-norm inherent in the tradition of non-use has been one of the reasons for many of the technologically capable among the 187 states forswearing their nuclear weapons options and joining the NPT. Their choices in most instances arose from a belief that nuclear states are unlikely to attack them with their weapons unless their core security interests, including existence as nation-states, are threatened. In 2008, there were only four key non-NPT states (India, Israel, Pakistan, and North Korea) and one other, Iran, which is a signatory but is believed to be violating its NPT commitments. Although their choices for nuclear acquisition have several regional and domestic-level causes, one thing is common to them all: these states have good reason not to take for granted the implicit guarantee inherent in the NPT on non-use and other associated treaties such as nuclear free zones, and the partial negative security assurances made by the NWS.
While most states have conformed to the NPT, there are variations in national positions on the question of the significance of non-use guarantees