As U.S. Central Command chief Gen. James N. Mattis testified to Congress in March, the downfall of Assad would be “the biggest strategic setback for Iran in 25 years.” Making it happen is not just a humanitarian imperative after the slaughter of more than 10,000 civilians, but a prime strategic interest of Israel and the U.S.
Obama is eager to avoid military action in Iran, but his strategy – striking a diplomatic bargain to stop the nuclear program – also narrows his options in Syria. A deal with Tehran will require the support of Russia, which happens to be hosting the next round of negotiations. Russia, in turn, is opposed to forcing Assad, a longtime client, from power by any means. If Obama wants the support of Vladimir Putin on Iran, he may have to stick to Putin-approved measures on Syria.