On the ground, the rebel groups similarly began pulling more closely together.
The Americans - in addition to their ill-conceived and ill-fated "train and equip" programme - began pumping in more money and hardware.
As a result, by the spring, the rebels had made significant advances in both the north, (Idlib province) and the south.
In public speeches, President Assad acknowledged that his forces suffered a crippling manpower problem that meant they would have to give up some areas in order to protect more important ones.