Peter Wehner mentioned Robert Kagan’s column earlier, and it seems to me its thesis is worryingly plausible:

Obama never meant to spark political upheaval in Iran, much less encourage the Iranian people to take to the streets. That they are doing so is not good news for the president but, rather, an unwelcome complication in his strategy of engaging and seeking rapprochement with the Iranian government on nuclear issues.
One of the great innovations in the Obama administration’s approach to Iran, after all, was supposed to be its deliberate embrace of the Tehran rulers’ legitimacy. In his opening diplomatic gambit, his statement to Iran on the Persian new year in March, Obama went out of his way to speak directly to Iran’s rulers, a notable departure from George W. Bush’s habit of speaking to the Iranian people over their leaders’ heads. As former Clinton official Martin Indyk put it at the time, the wording was carefully designed “to demonstrate acceptance of the government of Iran.”

Indeed. The president’s unprecedently deferential remarks toward Iran’s “Supreme Leader” are inexplicable if you’re sympathetic to the fellows currently being fired on but entirely consistent with a strategy of regime legitimization. Mr. Kagan adds:

The idea was that the United States could hardly expect the Iranian regime to negotiate on core issues of national security, such as its nuclear program, so long as Washington gave any encouragement to the government’s opponents. Obama had to make a choice, and he made it. This was widely applauded as a “realist” departure from the Bush administration’s quixotic and counterproductive idealism… His strategy toward Iran places him objectively on the side of the government’s efforts to return to normalcy as quickly as possible, not in league with the opposition’s efforts to prolong the crisis.

The administration’s behavior fits this depressing thesis — as I’m sure the mullahs have already figured out.