Iran and Russia also continue to deliver much-needed supplies to the Assad regime, including supplies for its air force which it uses to deploy cluster bombs and other ordnance against the rebels.
"External help also enabled Syria to create a new militia, known as the National Defense Force, to offset the losses incurred by the army," Stratfor says. "With the help of Iranian and Hezbollah advisers, the regime was able to rapidly train and deploy members of this militia."
"Over the past few months, fighting has regressed to battles of exhaustion and campaigns of attrition," Stratfor adds. "Instances where the rebels could quickly seize a major city in only a few days -- as they did in Raqqa -- are the exception rather than the norm."