The interim deal signed in Geneva by the P5+1 and Iran is meant only to put “more time on the clock” in order to negotiate a final deal – a comprehensive agreement that will ensure that Iran backs away from its military nuclear ambitions. As the international community embarks on its most difficult proliferation challenge yet, what lessons can be drawn from confrontations with other determined proliferators? What model best applies? In addressing this question, the article looks at encounters by the international community with other proliferators, and concludes that until Iran makes the strategic decision to reverse course in the nuclear realm, there is little chance that a true and lasting deal will be achieved. Continued pressure is the key, and therefore keeping an eye firmly on the leverage at its disposal is the only hope the P5+1 have to compel Iran to finally make that choice.