In the world today there is a large gap between the number of states that could easily obtain the military power of nuclear weapons and the number of states that actually choose that power. Curiously, a number of states that sought that power at one time or another have abandoned it. Yet, in other states, the quest for nuclear weapons continues. What causes this variance in behavior?Scholars generally rely on one of three explanatory models to address this question. The security model argues that states develop nuclear weapons when they find them useful to bolster their own security and deter external threats. The domestic model finds that states develop nuclear weapons if it strengthens the regime internally to do so. Finally, the normative model suggests that a desire to reinforce positive aspects of a states identity will lead it to pursue nuclear develop or adhere to a prohibition against nuclear weapons. This paper evaluates the relative weight of these three explanatory models in the decision-making process of three very early nuclear-capable states. This paper codes the justifications made by political leaders in Great Britain, Canada, and Australia in the 1950s and 1960s. The purpose of this analysis is to determine the relative weight of three distinct and competing explanations for nuclear acquisition, and to suggest a means of evaluating additional cases nuclear and potential nuclear states. ..PAT.-Unpublished Manuscript [ABSTRACT FROM AUTHOR]