The fact is that the Russian plane, by Turkey's own admission, was in Turkish airspace for precisely 17 seconds. That's a little less time than it takes to read this paragraph aloud. The Turks shot it down anyway — and their allies publicly backed them, as loyal allies must.
NATO Secretary-General Jens Stoltenberg declared: "We stand in solidarity with Turkey and support the territorial integrity of our NATO ally, Turkey." President Barack Obama called his Turkish counterpart, Recep Tayyip Erdogan, to assure him that the United States supported Turkey's right to defend its sovereignty. But privately, they must have been cursing Erdogan. They know what he's up to.
This is the first time in more than 50 years that a NATO plane has shot down a Russian plane, and it happened in very suspicious circumstances.