Why is Iran choosing to defy the world withal the present dangers of a military reaction if Iran kept pushing things to the edge?
Does Iran want to develop nuclear power for peaceful utilization?
If that was the case then the European offer is very reasonable and I find it generous and it cannot be claimed (without rising suspicions) that this offer doesn't meet the needs for a peaceful program. Not only that, it even guarantees better support than if Iran depended on its own capabilities as Europe will be contributing with her nuclear expertise…but Iran refused the offer.
Does Iran want to get nuclear weapons?
Why not? The nuclear military power's been the ultimate dream the leaders of the region who want to protect their regimes from any possible plans of change and to have the ability to attack their enemies.
But Iran realizes the idea that there are many countries out there that are going to stop her from possessing nukes and once some countries feel that Iran is too close to getting the weapons, they will no doubt take the move and destroy the infrastructure of the nuclear program and Israel is a strong candidate for conducting the mission here. It's fundamental that a strike with conventional, high precision weapons that are available for many countries is enough to destroy the Iranian dream without the least defensive response from Iran who lacks the practical ability of defending the nuclear facilities.
So both of the above theories put Iran before an irrational choice as the current escalation doesn't indicate peaceful Iranian intentions and at the same time in contradicts Iran's defensive abilities…so why escalate?
I think that Iran is seeking a limited confrontation and Iran is calculating the possible gains and losses well in this confrontation and the results expected by the regime there are:
1-Having the Iranian nuclear facilities destroyed.
2-Preparing the country for a take over by the extremists; in the way despotic regimes make their calculations, the resultant is positive.
Iran thinks that this is not the appropriate time for the super powers to invade and change the regime in Tehran since the situation in Iraq doesn't encourage making such a move.
And if Iran waited until the situation resolves in Iraq before taking critical steps like resuming the nuclear program then that escalation will impose greater threats on the regime itself not only the nuclear facilities while an escalation at the moment will result in limited reaction from the world limited to as much as destroying the facilities only while giving the regime the chance to halt any remaining sign of the struggling weak democracy in Iran; the nuclear facilities will serve just like the 'Mill' in Orwell's "Animal Farm".
This scenario is not far from what we’ve seen in Iraq; Saddam challenged the world after facing growing internal crises which made him export his problems to Kuwait.
He was seeking a confrontation with the whole world in an incomprehensible way that looked literally like suicide but Saddam like any other tyrant knew the results; losing Kuwait but gaining the "legitimate" right to silent any voice of internal opposition since the country is under external threats making any opposition look like treason. And that stage will be the worst timing for starting an opposition movement while the government is calling for "national unity" to face the foreign threats.
Iran will push for a confrontation and whatever is proposed will not be viewed as convincing to Iran which will put the world before tow ways to choose from, either a limited confrontation that prolongs the lifetime of the regime and grants it more power on the inside OR success in possessing the nuclear weapons before the world makes the practical measures to stop Iran and Tehran is not willing to take a third option.