When several parties fight against a common enemy, this should have a uniting influence, but as always, when you put someone to the test, you learn about their true character.
So the IS is fought by NATO and Russia. Russian fighter planes operate in Syria because of this. And then one accidentally violated the airspace of the neiboring Turkey and was shot down! Russia enacted economic sanctions against Turkey because of this, and rightfully so.
Because realize the implications: What a psychopathic trigger-happy warmongering government does Turkey have? They knew it was a Russian plane and they knew it was there as part of fighting the enemy of NATO and Russia, the IS. Turkey is in the NATO. They couldn’t have possibly been so insane as to believe that Russian plane might have intended to attack Turkey. You don’t react like that unless you want conflict. (And let’s not forget how NATO themselves treats their putting pressure on other countries through close military presence like a right they have. They are experts at offending.)
Recently there was another case of a Russian plane scratching that Turkish airspace, and again the NATO (not just Turkey) plays the outraged.
The motivations for all this are mostly known, NATO being an instrument of a Cold War mindset that never really ended, always keeping the separation intact and discarding good will from Russia (pretty much what USA did and does with Iran), but there are also some less commonly known non-secrets, and cases like these airspace violations might actually serve to fully dig up the ugly truth.
You see, while the IS is an enemy of NATO and Turkey is a NATO member, Turkey doesn’t really consider IS their enemy. They have quite an interest in its continued existence. (They’re not the only ‘Western ally’ with such an interest.) And this is what is being brought closer to the surface of public awareness with such incidents. And that can be considered healthy. It is ‘Teacher Discord’ at work.
These things reveal more and more the underlying nature of shifting allegiances of the West (the USA and its lackeys), determined by who serves the imperial agenda. In such a system, there are no friends or enemies based on values of decency. It is all profoundly egoistical; a game of sociopaths, of fear, cowardice, denial of responsibility and fanaticism.