Moscow's military intervention in Syria took a sobering turn this weekend as Turkey scrambled fighter jets, accusing Russian warplanes of violating its air space. Turkey has summoned the Russian ambassador over the matter, and NATO condemned the incursions as an "extreme danger." (Al Jazeera, CNN, Daily Sabah) Apart from the obvious dangers to world peace (such as it is), this development holds grim implications for the Syrian Kurds—the most effective military force on the ground against ISIS. Turkey, afraid that a Kurdish autonomous zone on its southern border will inspire its own Kurdish population to rise up, has been cynically labelling the anti-ISIS Syrian Kurds as "terrorists," and seeking to establish a military "buffer zone" in Kurdish territory in norther Syria. Since Turkey and Russia are bitter regional rivals, Moscow's intervention risks drawing the Kurds into the geopolitical game.