If your allies are assholes and you are sworn to go to war for them . . . .

Putin Sends Air-Defense Missiles To Syria To Deter Turkey

This is a modest and not unreasonable response to the Turks deliberately shooting down a Russian plane with the flimsiest of stupid excuses.

The Turks are and have been pretty much AWOL from the war on ISIS, being far more concerned to get rid of Assad, whom they perceive as a client of Iran and friend of Shiites, than to crush ISIS, a Sunni state/organization.

The US and the Europeans are opposed to every form of Islamoextremism, of course, and pretty much nobody in the entire region shares those priorities, excepting maybe Israel, the government of Jordan, and (up to a point) the government of Egypt.

Did you need more proof we should have dropped out of NATO when the Soviet Union collapsed?

From the story.

Putin has dismissed Turkey's claim that the Russian warplane intruded its airspace [the media report it was in Turkish airspace for 9 seconds, crossing a sliver of Turkish territory on a routine flight - PV], voicing particular annoyance about Ankara turning to NATO instead of speaking to Russia, "as if it were us who shot down a Turkish plane."

NATO Secretary-General Jens Stoltenberg in turn said that the downing of the plane "highlights the need to strengthen mechanisms to avoid such incidents in the future."

"We should not sleepwalk into unintended escalation," he wrote in an op-ed that is to be published Thursday and was made available to The Associated Press.