Recent revelations of Iran’s hitherto undisclosed uranium enrichment programs have once again incited western fears that Tehran seeks nuclear weapons’ capability. Their fears seem motivated by more than the concern for compliance with the Nuclear Nonproliferation Treaty (NPT). Rather, they seem strongly connected to the western moral assumptions about what kind of government or people can be trusted with a nuclear arsenal. In this paper, I critically examine the western assumptions of the immorality of contemporary nuclear proliferation from an international (...) ethical stance that otherwise might be expected to give it unequivocal support – the stance of Kantian nonideal theory. In contrast to the uses of Kant that were prominent during the Cold War, I advance and apply a sketch of a Kantian nonideal theory that specifies the conditions (although strict conditions) under which nuclear proliferation for states like Iran is morally permissible even though the NPT forbids it. (shrink)