Iran is capable of moderation, it heads that way at times, events unfold, the clergy gets a rally, and the hard-line wins. There is no the hard right clergy there is a bit frightening, just as the hard right Politburo elements were rather frightening. But Nixon and Brezhnev did talk, detente did develop, and while still two different countries vying for influence all the time, it is worlds better than it was.
This is the path with Iran. Engage. The stumbling block is isreal (and of course the added dimension of extreme islam. But is extreme islam any different than extreme authoritarian communism?