MoROmeTe the Dacian has sadi it very well. If Iran is acting out of paranoia then who can blame them? Just look how a staunch ally of th West 20 years ago has now been treated - how much worse would it be for them who have never been particularly friendly.
Ouside of Turkey and Isreal, Iran has the best developed democratic models in the Middle East. It is gradually (with one step back, on occasion) developing those democratic institutions - this is ironic considering how much influence the religious wings of American politics seems to be growing (perhaps this is where Iran is going wrong...).
So far, as we know, Iran has broken no laws - can the same be said of Israel? I do not condemn Israel for having nuclear weapons (though how it intends to use them is quite beyond me) BUT I cannot understand how the West regard it as perfectly reasonable for Isreal to have WMD but others not to. I, perhaps, there was even a hint of a degree of even handedness, we might get further in negotiations.
And we wonder why we are unpopular and mistrusted. If we were Iranians (or Arabs) would we trust the West?