The ‘fog of war’ got murkier given Turkey’s shoot-down of a Russian SU-24; putting an impulsive Russian leader into heightened tension with questionably ‘soft’ on ISIS Erdogan.  He  has been quick to object to near-border flights by Russian aircraft (understandable, but not they way they reacted in this ‘barely’ momentary, if at all, intrusion into their airspace), while reluctant to disrupt the illegal sale of black-market Oil by ISIS (until finally Russia and France and the US, hit the transport trucks, which could have occurred long ago).
 

We won’t go so far as saying that Turkey (or others?) aid ISIS; but complexity in an overall manner can be slightly simplified by acknowledging that Turkey, as well as Saudi Arabia, are vehemently opposed to Assad; hence their hatred for Russia and Iran being the primary supporters; with the Russian Air Force of course functioning in a way that bails Assad’s tail out of his mess. That’s a reason why once ISIS miscalculated and attacked Russia’s commercial jetliner  and you had Moscow swing resources into ‘actually’ focusing on ISIS; so much so that it’s embarrassed Washington, who could have brought this high firepower level to bear much earlier.This is why so many have implied that the tactics, dubious at best, were to ‘prioritize’ moving against Asad, if not indirectly aiding ISIS (or the rebels, or both; it’s impossible for most to tell for sure) before going against ISIS in a more serious way. 

Russia’s intrusion into the region threw that formula to the curb; and once ISIS attacked Paris, there was no further question of how this would go. Turkey was irate, and perhaps Putin means that when he says ‘stabbed in the back’. There had been some military cooperation between Russia and Turkey previously. Of course now the question is not just ‘why or whether’ Turkey was trigger-happy; but more to the point: is this a form of response to throwing off Russia’s goals, which already had shifted more to combating ISIS; finally was nudging toward creating a workable relationship, if not coalition, between Russia, France and of course the U.S. (with Britain in the wings). So do we back NATO member as well as primary USAF launching point (Incerlik AFB) or question if Mr. Erdogan has ulterior, and slightly pro-Islamist objectives. Hmm… consider his domestic clampdown on press and other freedoms lately; and you might see a pattern. I suspect that’s why NATO didn’t jump onto a unity bandwagon today; but rather urged Turkey to settle-down and not provoke retaliation from Moscow (which is not possible to determine if that’s too late or not).