Just goes to show why the USA needs to go isolationist. Obama the Undecider waffles around until the UN gets through dicking with itself to craft a deal whereby NATO provides armed force, with the Arab League "contributing" mostly by selling us high-priced fuel and services. This will of course not happen until the intervention has become pointless. Then China and Russia will reap the profits, either being the ones who delayed the measure until it had no practical possible outcome, or if by some near-miracle the rebels win, by being out of it. (Trust me, not many will forgive the ones who helped them out, and those who might do so will remember the hesitation long after they've forgotten the intervention.)
If the USA decides to act unilaterally, there is only a small chance of it being to our benefit. If the USA decides to wait for the UN before acting, there is virtually no chance of it being to our benefit, plus the nominal benefactors (the rebels) will be massacred and will blame us for hesitating. Either way we'll be resented even more in the Arab and Muslim worlds, if only for having the strength to act.