To start with a concrete example: Russia and Syria and Iran are enemies of ISIS, one of the final obstacles to firm regime control of Syria. So any reprieve to ISIS granted by America’s abrupt withdrawal may be temporary.
But a larger and more critical point is that the challenge facing Russia and its client regime in Syria—not just consolidating control of Syria but rebuilding a devastated country—leaves Russia with no interest in the further destabilization of the Middle East. Which is good, because it’s hard to imagine the Middle East getting much more unstable—especially along the fault line between Iran and Syria on the one hand and Israel and Saudi Arabia on the other—without another disastrous war breaking out.
Russia has already shown signs of being able to play a constructive role here—a fact that, oddly, has been emphasized even by some who buy the “gift to Putin” thesis. Hal Brands of the American Enterprise Institute—in a Bloomberg Opinion essay titled, “Putin Conquered the Middle East. The U.S. Can Get It Back”—notes that “Putin has shown diplomatic flexibility, keeping the lines open to nearly all players throughout the region.”