One, Russia is not chasing off American F-22s in Syrian air space. Russia is crossing the deconfliction line (which is kind of like a new DMZ in some ways), and American planes are warning them off.
Two, Russia hasn't won the Syrian multi-war and talks are just the simulation of peace talks among friends of Assad. I did mention that Russia was trying to fake victory to convince foes that the war is over.
Second, Russia started the rumor that America let 4,000 ISIL fighters flee Raqqa to continue the war against Assad. I thought there could be a grain of truth to this given that Assad did exactly that with ISIL fighters captured in Lebanon; and given that I doubted that our Syrian Kurdish allies were eager to die in order to kill ISIL fighters in the city. So I could see us bending to local allies while sticking it back to Assad. Apparently not.
On another issue that doesn't involve Russian lying (what are the odds?) Strategypage notes the manpower Assad has:
Iran has 24,000 fighters in Syria to make sure that does not happen. Some 62 percent of the Iranian forces are Shia mercenaries from Afghanistan, Pakistan and elsewhere. Another 35 percent are Hezbollah (Lebanese Shia) and the rest are Iranian trainers and technical advisors. The Syrian armed forces have about 200,000 men on the payroll but most are not effective for offensive operations (that’s what Hezbollah and other Iranian mercenaries are for) and useful mainly to provide local security. As ISIL loses control of eastern Syria the Assads are finding it more difficult to provide enough loyal Syrians to maintain order in the expanding Assad territory. Iran sees this as an opportunity to provide Iranian Shia mercenaries on a long term basis to deal with that. This gives Iran more control over eastern Syria and the Iraqi border. This is key to maintaining a land route from Iran to Lebanon for the coming battle with Israel. Finally Russia has about 5,000 military and contractor personnel in Syria providing the Assads with air, intel and logistical support.
Which makes it clear that 80% of Assad's fighters are not in fact Iranian proxies (Hezbollah, the Shia foreign legion, and some portion of the Syrian militias) as I doubted in this post. I suspect that McMaster's claim is actually about the pro-regime shock troops that can go on the offensive in contrast to the vast majority of Assad's ground forces that are either static defensive forces or support troops.
The casualty toll--although some claim higher levels they may be too high so I will stick with the Strategypage assessment--is 350,000 dead since fighting began in 2011 (although fighting didn't really kick in until 2012, I think). A third are civilians; about 18% are Syrian armed forces; about 18% are Syrian or foreign militias (Hezbollah and Iran's Shia foreign legion); 16% are dead rebels; and 16% are dead ISIL fighters. Note that some rebel/ISIL dead are from intra-rebel fighting by rebels and ISIL. Also, note that the total exceeds 100% from rounding.
And of course, assuming what Russia says is a lie until proven otherwise is always the safe option.
Read all of the Strategypage post, of course.