NPT allows iran to enrich uranium, however no person in its right mind thinks that iran will 'not' make a bomb. US is all tied up in Iraq and other places. So i think iran will enrich a lot of uranium , build a bomb then "withdraw" from NPT via national interest clause of NPT that allows for such withdrawals, and declare itself a nuke weapon state on the lines of NKorea. I am not sure what US/UN can do to prevent this sequence of events .
