Middle East Syria: Can Trump's anti-Iran strategy survive hostilities with Turkey?

As Russia, Iran, and the US strive to establish facts on the ground to maximize their chances of shaping postwar Syria, Turkey is posing a challenge to a key piece of the Trump administration’s emerging policy.

Lefteris Pitarakis/AP

Turkish tanks rolled into northern Syria Sunday, attacking Syrian Kurdish forces that have been instrumental US allies in the fight against Islamic State militants.