pavel baev, what do we know of the extent of the russian involvement right now in syria? >> very little is actually known for fact, and what is known doesn't make much sense because what russians are saying is, yes, we are supplying small arms and munitions and personnel carriers and some military advisors and some technical personnel. this sort of military weapons doesn't need any technical advisors and personnel. they're elementary. so the feeling is that the russian military delivers produced political spin and that was deliberate. >> ifill: steven simon, do we think we're talking about advisory help or combat help? >> well, we know that the russians are worried about this -- the viability of the syrian regime right now. the syrian regime has absorbed pretty serious losses in the past year. 2014 hay that did a good year. 2015, not very good. they're under pressure in the south and now in the east, lost palmyra. they've got a demographic problem. it's not clear how long they can actually keep up the fight. for the russians, the viability of this regime is extremely impo