What the US was doing before Israel blew up its efforts.
The idea that iran has any interest in using nuclear weapons is so absurd that it's incredible any one could take this propaganda seriously. Every relevant country has at least second strike capabilities against Iran, so it would be suicidal in the extreme -- it's also highly likely that the handful of nukes they'd have would be mostly intercepted. They haven't even developed second strike themselves, so they'd almost certainly lose any nuclear capacity on first attempted use. Iran's capacity for nuclear agression with nukes, is tiny.
Iran having a nuclear weapon would be one of the most stabilising outcomes in the middle east, as it would prevent israel (which is the most violent, destablising state in the region) from acting with impunity. This is why israel has, for 30 years, been complaining that iran is "months away" from a bomb, and why for 20 years its being trying to precipitate a war to drag the US into.
Iran having a nuclear weapon is the best possible outcome for global security, precisely because its the only configuration of events which prevents israel from waging wars of aggression on its neighbors (syria, iran, et al.).