The shock of realizing their was no hope of American intervention surely hurt the Syrian rebels. But Assad was unable to deliver a killing blow to the rebellion since that deal was signed. Assad may be stalling the completion of the chemical weapons deal, but the situation on the ground shows that the war will go on.
Assad is still trying to clear areas west of Damascus in his Rump Syria:
Syrian refugees are streaming across the border with Lebanon into this town to escape a punishing Syrian regime offensive in the Qalamoun region just across the border.
Newly arrived refugees speak of harsh and perilous conditions in Yabroud, the largest town in northern Qalamoun still in rebel hands, and the nearby villages. The strategic area north of Damascus is under heavy artillery shelling and air strikes, including barrels packed with high explosive tossed out of helicopters, known as barrel bombs.
And the rebels are still capable of attacking south of Damascus, as I discuss here, in our Southern Front based out of Jordan.
Remember, Assad has been able to go on offense in large part because he abandoned much of Syria to fight for a smaller area.
This has not worked. And now it is a war of attrition that his side has already suffered much--way out of proportion to their enemies--in fighting.
I still bet that Assad's side breaks first. But our failure to support rebels to the same degree that Iran and Russia support Assad makes the outcome far less certain than I'd like. And it raised the cost. Winning a war quicker by waging it more energetically is a less appreciated method of saving lives in war.