From article by Walter Pincus in the Washington Post, 9/5/13
"As I wrote Tuesday, the precedent worth recalling is Operation Desert Fox in December 1998, in which the Clinton administration went after Iraqi leader Saddam Hussein's facilities for weapons of mass destruction over four days.
Although the operation almost immediately faded from the American public's mind because it was followed quickly by the House impeachment debate, it did destroy Iraq's WMD infrastructure, as the Bush administration later discovered."
There were also no collateral deaths and no retaliation by anybody, part of the reason it was so quickly forgotten, along with people so concentrated on the The Really Important Issue Of Clinton Lying About Sex (which Operation Desert Fox was supposedly an annoying distraction from).
In fact, it is clear from how it has been described, Pincus is on the money, and what is being planned is essentially a rerun of Operation Desert Fox. If it happens (not all that likely given a likely no vote in the House of Reps), the chances are very high that the outcome would be about the same: a successful degradation of Assad's capability to deliver chem weapons, with minimal collateral damage and no retaliation by anybody. Iran is already talking softly.
Yes, lots of things could go wrong. The most likely could arise from having gone to Congress and given McCain a tidbit in the form or promising more backing for the rebels. While there is a possibility of the "moderate" faction of rebels to win, it looks much more likely that if Assad falls radical Sunnis will take over who will make Mohammed Morsi in Egypt look like Martin Luther King, Jr. It is indeed a very narrow space between degrading Assad's chemical weapons delivery systems sufficiently and tipping the war to the side of the rebels.
The other complication, rarely mentioned by most people, who mostly go on about ridiculously unlikely scenarios, is that Syria is one of the handful of nations that has never signed the 1925 treaty banning chemical weapons use. From their perspective, they have done nothing wrong (although they have been formally denying doing it, with the Russians backing them on that), and Juan Cole reported twice that it may have been a local commander either going rogue or just goofing in this last attack, with most reports saying there have been 9 or 10 attacks, but with only small amounts of sarin, not enough to provide awful photos of children who died excruciatingly.
I cannot leave this without noticing how pathetic a lot of the Dems in Congress have looked on these matters for some time. There is a tendency to be knee jerk responding to the last major event. So, Dems voted for Vietnam because of Munich, only to be embarrassed when it was a mess. Then they voted against the first Gulf war, because of Vietnam, only to be embarrassed when it turned out mostly OK. Then they voted for invading Iraq in 2003 because they had been embarrassed over voting against the mostly successful first Gulf war. Now we see most of them about to vote against this small exercise because of being embarrassed over having voted for invading Iraq. None of them remember the highly successful Operation Desert Fox that this is based on, and which was not voted on.