Syria's uprising offered the possibility of a strategic defeat of Iran. In this scenario, Iran would be weakened by the collapse of Bashar Assad's regime, its single Arab ally and a vital link to Lebanon's Hezbollah militia. Isolated, Iran would become more vulnerable to international pressure to limit its nuclear program. And as Iran's regional influence faded, those of its rivals — U.S. allies Turkey, Qatar and Saudi Arabia — would expand.
Instead, events in Syria are spinning in Iran's favor. Assad's regime is winning ground, the war has made Iran more comfortable in its nuclear pursuits, and Iran's gains have embarrassed U.S. allies that support the Syrian uprising.
What's more, Iran has strengthened its relationship with Russia, which may prove to be the most important strategic consequence of the Syrian conflict, should the United States continue to sit it out.