You make the mistake of believing that all your enemies are suicidal. I bet you thought (still think) that the Soviet leadership was all a bunch of fanatics and madmen. Maybe so, but they had the good sense to know that starting a nuclear war is not it anyone's best interests.
And anyway, its not as simple as "Iranians hate our freedom and want to destroy the western world". Aside from the embassy thing, I can think of no example when Iran has attacked the US. And they would surely not do so if they got The Bomb, because as someone mentioned, that would pertty much be the end for them. America however, possesses several thousand nukes, and its plans to attack Iran at the first possible opportunity are not exactly a secret.
also, please don't make such stupid, simplistic statements like "all terrorists are Muslim". What about Timothy McVeigh, or Irish terrorists, or several dozen US backed terrorists organizations, both past and present, or in fact, the US itself.