I would have two reactions or two answers to the question.
First off, it's important to recognize that it's not a bilateral fight. One of the things that make this so extraordinarily difficult for everyone involved is the fragmentation that's involved and the number of groups. Our estimate is that 74 outside nations have people fighting right now in Syria. You also have changing alliances, which makes it extraordinarily difficult.
Second, with respect to rising and falling fortunes, I will say, as Senator McCain pointed out, that we have seen more people killed in just the last several weeks since, ironically, the peace negotiations began than in any other time in the conflict.
The other piece that's important is that clearly time is not an ally of the rebels. Assad has made it very clear. We've seen the negotiations fail over and over again, in part because there appears to be no sense of urgency on the side of the government, of course, to bring about a solution. The passage of time is something they're comfortable with.