Q.What should the U.S. due right now?

A. Nothing. The U.S. and especially president Obama himself should remain as quiet as possible about the unfolding events in Iran. There is no upside to commenting; if he were to say something good about the protesters and they are eventually suppressed then he's left being forced to deal with a government in Tehran that he would have effectively declared illegitimate. On the other hand, if he recognizes the regime's "win" and the government collapses then how would he recognize the (presumably) more reform oriented government that takes its place? And all of this is to say nothing of latent anti-Americanism and suspicion that runs through Iranian society.

All and all, President Obama has so far followed a smart path. In the coming days the temptation to respond in favor of the protesters may grow. There will be intense pressure from Republicans to say or do something, maybe even something as rash as recognizing Mousavi as the winner. President Obama must resist the temptation to do this. Through sub cabinet spokesmen and the V.P., the White House can express concerns about the potential human rights violations against the protesters and also about the silencing of media. But through it all the president must remain silent and resist the temptation to take sides in the power struggle.