Who did it? We could never really know....and so, what is to be done about Syria?

There is a very sad drama playing out in St. Petersburg, Russia, with the G20 leaders face to face in one room, for periods of time, including a formal dinner with conversation about Syria, with no consensus, and no likelihood of any movement toward a resolution of the Syrian crisis.
At the core of the disagreement, apparently, is who is responsible for the chemical weapons that were inflicted on the Syrian people on August 21, just last month. Russia blames the rebels, while the U.S. and France and a few other countries hold the Syrian regime of Assad accountable.
The United Nations inspectors, while focussing on the evidence they gathered, will not be able to discern the agent of the slaughter of some 1400 people, over 400 of them children. Yesterday's release by the New York Times, of a video purporting to be the assassination of regime supporters by the rebels, in cold blood, does nothing to bring world leaders to the side of the rebels. Neither do reports that suggest some 15-20% of the rebels are AlQaeda affiliates, apparently that translates to between 15-20,000 of the total of the rebels.
It would seem that the debate in the U.S. Congress is taking a turn toward rejection of the proposed resolution from the Obama administration, whose calculus on this issue has not gone according to what might have been their script. The British Parliament's rejection of the military strike concept, along with confusion as to what might result from a U.S. strike has lawmakers in the U.S. putting their foot on the brakes, not the accelerator of this proposal.
World Court, International Criminal Court, the United Nations, NATO...all of these have been proposed by several legislators in Congress, from both parties, as avenues to explore, prior to or perhaps never resorting to the military strike.
Everyone, however, internationally and within the U.S. does seem to agree that the cessation of the slaughter has to stop....but how to get to that termination seems to be a gordion knot which no one or even a cadre of countries can untie.
Reports from the inspectors will be available in two or three weeks, probably after the U.S. Congress votes, and Ban Ki Moon, Secretary General of the UN has asked the U.S. President to hold off inflicting the attack until after their report is released. Hawks, like John McCain and Lindsay Graham will not likely remain patient that long; they have been waiting for the administration to strike Assad's regime for two years.
We continue to hold out hope for the various processes that exclude, even preclude, military action, given that the world knows it will not be a solution, but merely a punishment, and not a very effective one at that. There is always the possibility that in this proxy war, following a strike by the U.S. even with allies, the Russians will take the opportunity to up the ante by supplying additional weapons, support and further enmeshment of their forces with the regime, while the U.S. will inevitably become more engaged in response.
And that scenario has to be playing out in the minds of even the most supportive advocate for the Obama proposal to strike.
It would take very little for this proxy war to escalate into a Middle East conflagration, the only winners of which could be the radicals in establishing one or more Islamic states. And that prospect is not one the world can really afford, or tolerate.