While most professionals and scholars share negative view of nuclear proliferation, small but influential number of them claim that more nuclear armed states may bring more stability to the international system. This debate between proliferation optimists and proliferation pessimists is yet to be resolved. This paper should contribute to the debate over important disagreement between the two schools, namely the issue of allegedly raising prospects of preventive war. It first discusses plausible theoretical explanations for decisions (not) to intervene in a situation when prospective attacker already seriously considered such motion. Then follow five illustrative historical cases when the preventive strike was either contemplated, or actually took place.
