There is no good reason to intervene in Syria. The current status quo is a win win for the USA. Let the Sunnis and Shiites have it out against each other. Let the Jihadis turn their suicide bombers against Iran and her allies, which currently include Russia and China. The long term threat is Iran and her nuclear weapons. By letting the bloodbath continue in Syria, the Sunni world, the vast majority in the ME, will turn its vengence against the Shiite trio of Iran, Assad, and Hezbollah, with Russia and China to boot. So again, why should the United States get involved when the status quo is to our favor.
I say we arm both sides very heavily and then get out of their way, let them tear each other to shreds.