A reader writes:
I think Obama's Mousavi-Ahmadinejad comparison is strategically brilliant. From our perspective, it realistically lowers expectations if Mousavi does take power. His ascension will have only subtle effects on Iranian foreign policy. Mir Hussein is not the Iranian Václav Havel. He is an insider who'll have to deal with the same power blocs Ahmadinejad does. Still, not expecting Mousavi to call for an Israeli holocaust and to deny the German one.
From Mousavi's perspective, being mildly put down by Obama shows that he's not a secret puppet of the US government. It lets him show his nationalist credentials. This defuses Supreme Leader Khamenei's main attack on the Islamist reformers.