After President Trump’s Thursday evening airstrike on a Syrian airbase that launched gas attacks on civilians, the big question was how Russia would respond. Trump reportedly called Russia to let them know the airstrike was coming, a smart strategic move designed to avoid escalating a police action into a great powers conflict. But Russia has significant strategic interests in Syria – so much so that Russia has put boots on the ground and Russian weaponry in the field. Russia sees upholding Assad’s regime as a key element of knitting together a Middle Eastern sphere of influence ranging from Iran to Lebanon.

It’s therefore not a major surprise to see Russian dictator Vladimir Putin respond to America’s airstrike with aggressive diplomatic and military action designed to ram home the message that Russia is the dominant force in the region, not the United States. Russia has now said that its military will help strengthen Assad’s air defenses against the United States to prevent further airstrikes; Russia has condemned the missile strike as “an aggression against a sovereign state in violation of international law.”

Russian Prime Minister Dmitry Medvedev stated that the attack brought the United States to the brink of a “military clash with Russia.” And now, Fox News is reporting that a “Russian warship has entered eastern Mediterranean heading toward 2 US Navy destroyers that launched airstrikes last night.”

It’s highly unlikely that the Russian military wants to enter a shooting war with the United States. They’d lose that war, and lose it handily. With that said, any sort of direct conflict would be awful for the United States and for the world. So now Russia is playing a game of chicken, hoping Trump will blink.

There’s a strong case that Trump will blink, too, given that the United States’ strategic interests in Syria are minimal at best. That’s why Trump should clearly define the US goal in Syria as maintenance of refugee zones and prevention of use of weapons of mass destruction, as well as protection of Kurdish bases of support in the north and pressuring Russia to replace Assad. A full-scale attempt to depose Assad will now invoke central Russian interests – and while Putin could back down, there’s a real possibility he wouldn’t out of desire to posture to his own citizens and the global community.

All of this demonstrates that the Obama administration’s continuous appeasement of Russia has serious consequences. Further appeasement shouldn’t be on the table. But the Trump administration should certainly tread carefully.