Exactly. NATO is obliged to come to defend its members from an attack, not jump in when one of the NATO countries attacks someone. This was done precisely do avoid another WWI. Europe doesn't want a war with Russia, nor do they care much for Turkey lately. I'd say, the Turks just invited the Russians in with that plane. That was a very shortsighted thing to do, given everything. Dunno if this was planned or not, but if Putin intended to bait them into giving him a casus belli that way (definitely wouldn't put it past him), then they took it hook, line and sinker. And even if he didn't plan for that, it's still playing right into his hands. Russia is bombing ISIS now, so they're "good guys" in that region, at least. TBH, I'm looking forward to hearing what Russians have to say about that.