After receiving criticism from the entire world as well as the American left for his "unilateral" approach to the war in Iraq, President Bush decided to step aside on the issue of the Iranian nuclear threat and let the Europeans and the "international community" handle the problem.
After several years of failed negotiations, we now see the fruits of Europe’s "soft power" approach. Confronted with nothing other than European hand-wringing, Iran has had years to disperse its nuclear sites, cement economic ties with China and Russia, threaten the world with an energy crisis, and now to take pre-emptive moves to mitigate the effect of economic sanctions that the Chinese and Russians will probably veto anyway. Iran’s nuclear program is so advanced, and the regime is so uncompromising in its insistence on its right to develop nuclear power, that there’s already an air of inevitability about Iran getting ahold of the bomb.
The core problem with the European approach is that the EU clearly views a military attack on Iran as a worse outcome than Iran acquiring nuclear weapons. Iran, of course, realizes this, and that’s why the "soft power" approach is worthless unless it’s applied against a really weak adversary, or it’s ultimately backed up by some kind of military threat. It’s like putting cops on the street that aren’t allowed to use force against criminal suspects. Negotiation is all well and good, but some criminals just can’t be reasoned with.
The feckless European position vis-a-vis Iran does not mean, however, that the Europeans have become ideological pacifists. For example, the French have no problem throwing their weight around their former colony of Cote d’Ivoire, even though the local population has made it abundantly clear that they want UN troops, and especially the French, out of their country.
So the Europeans don’t mind a little military adventure when the opportunity arises — they just don’t want to engage in one against an adversary strong enough to put up a fight.