The Obama Effect, Ctd

In response to this survey, Drezner asks:

I do wonder just how much leverage this kind of soft power carries with it.  Consider the ability of the U.S. to enact multilateral economic sanctions.  The Bush administration, at the depths of its unpopularity, was still able to get the UN Security Council to pass three rounds of sanctions against Iran, as well as measures against North Korea.  The Obama administration, despite a serious effort to open a dialogue with Iran, is encountering resistance from China, Brazil, and Turkey in its efforts to craft another round of sanctions. 

All else equal, it's better to see these numbers going up.  I'm just unsure of how much this translates into usable leverage.