well if iraq and north korea has taught us anything, getting nukes is the only way to NOT to get invaded.
iran is already an 'evil' country with little respect from the rest of the world, what do they have to lose?
US army is so stretched thin at the moment, election year, lots of anti war sentiment (esp. in europe), and the like, this is a VERY smart move by iran.
Now i'm not supporting nukes, but as a side note, who SHOULD have nukes? When the US pulled out of reducing nuclear stocks, they set the benchmark for the rest of the world. It is a case of monkey see, monkey do...big military, nukes, extreme religeous leadership, unilateralism...
Not so different if you ask me...