First, Mr. Obama should contact Mr. Mousavi to signal his interest in the situation and Mr. Mousavi’s security. Our own experience with dissidents around the world is that proof of concern by the U.S. government is helpful and desirable. The administration was wise to send Vice President Joe Biden to Beirut on the eve of the Lebanese elections, and his presence there helped galvanize the anti-Hezbollah coalition. Mr. Obama’s political capital in the region has only expanded since his June 4 Cairo address. If Mr. Mousavi deems talking to the American president not to be politically helpful, then he can refuse the call. But that should be a judgment for him to make.

Second, Mr. Obama should deliver another taped message to the Iranian people. Only this time he should acknowledge the fundamental reality that the regime lacks the consent of its people to govern, which therefore necessitates a channel to the “other Iran.” He should make it clear that dissidents and their expatriate emissaries should tell us what they most need and want from the U.S. This could consist of financial resources, congresses of reformers, workshops or diplomatic gatherings. The key is to let the reformers call the shots and indicate how much and what U.S. assistance they want. Simply knowing we care, that we are willing to deploy resources and are watching their backs — to the extent we can — often helps reformers.