In this Christmas season, President Donald Trump has given Turkey the green light to massacre our Syrian Kurdish allies.

The Kurds provided the main fighting force that took on ISIS inside Syria. Working closely with U.S. special forces, they provided the fighters that crushed ISIS in Syria and ultimately smashed the jihadi capital of Raqqa. Their soldiers, including a tough female army, suffered severe casualties.

Yet the U.S. president casually consigned the Kurds to potential slaughter via Twitter and an ill-informed phone call with Turkish president Recep Tayyip Erdogan. He did this against the advice of his top military commanders. He did this despite the pleas of outgoing Secretary of Defense James Mattis, who resigned over this issue.

In so doing, Trump displayed an ignorance of Mideast politics, geography, and Turkish intentions so great that it raises (again) the question of his mental competence (see Article 25 of the U.S. Constitution).

The more immediate question: Who will save the Kurds from Turkey and Trump?

Trump’s Kurdish debacle began with a phone call two weeks ago with Erdogan, after which the president suddenly tweeted he was pulling all 2,000 U.S. troops out of Syria. Erdogan has long urged Trump to break the U.S. relationship with Syrian Kurds. (He fears the autonomous area they carved out in Syria will inspire Turkey’s Kurdish minority.)

The Turkish leader apparently convinced Trump that U.S. troops were no longer needed in Syria to wipe out remaining ISIS pockets and to prevent a jihadi resurgence. “President @RT_Erdogan has very strongly informed me that he will eradicate whatever is left of ISIS in Syria … and he is a man who can do it plus, Turkey is right “next “door,” the president tweeted.

Had Trump absorbed a single briefing on Syria or Turkey he could not have posted such an ignorant tweet.

For starters, Turkey has never shown any interest in fighting ISIS, but rather has focused on crushing the Kurds. Indeed, Turkey was notorious for letting ISIS fighters cross back and forth across its border with Syria.

In 2016, I visited Rojava (as the Kurds call their autonomous area in northeastern Syria), crossing the Tigris River by boat from Iraq. In the Rojavan capital of Qamishli, a Kurdish military spokesman showed me material seized from ISIS headquarters in towns liberated from ISIS. This included schedules for ISIS vans traveling back and forth to Turkey, as well as lists of Turkish clinics and hospitals that treated wounded ISIS fighters, and the amount of the payments for their treatment.

If Trump had mastered Middle East 101, he would know that Turkey has always been loathe to crack down on ISIS because the jihadis were fighting Erdogan’s real enemies: Syrian president Bashar al Assad — and the Kurds.

Moreover, the Turkish army hasn’t the capacity to reach the remaining pockets of ISIS in Syria, which are far from the Turkish border.

In other words, Erdogan’s promise is bunk.

What is “right next door” to Turkey — to use Trump’s words — are the Kurdish towns and villages of Rojava. If Trump withdraws U.S. forces within 100 days, as promised, they are what Turkey will attack.

“Within hours [of U.S. troops leaving] Turkey will start its air bombardment,” says Columbia University’s David Phillips, “followed by (Ankara backed) Free Syrian Army militias committing atrocities, just like in Afrin.” Phillips is referring to the Turkish army’s air and artillery attack on the Kurdish city of Afrin near the Turkish border in March 2018.

After Afrin fell, Turkish-backed Syrian militiamen kicked tens of thousands of Kurds out of the city and many fled further east to Rojava. “Now there is no place left for Kurds to flee to,” says Phillips, author of The Great Betrayal: How America Abandoned the Kurds and Lost the Middle East.

If Trump leaves our Syrian Kurdish allies alone to fight Turkey, ISIS fighters will be free to reemerge from hiding. Kurdish troops will be forced to return home to defend their families. Without any air force, their towns will be defenseless against Turkish bombs.

So what is to be done to prevent the slaughter of the Kurds?

If Trump were a normal president, his advisers would try to convince him to delay the withdrawal. They would urge him, at minimum, to warn Erdogan against attacking the Kurds — and to establish a no-fly zone over Rojava, preventing Turkish air strikes. Even Erdogan appears nervous about the precipitous U.S. exit, so he might listen.

Meantime a delay in the withdrawal would at least give the Kurds a chance to negotiate with Russia and the Syrian regime of Bashar al-Assad to see if they would offer protection against Turkey in return for a sharp limit on Kurdish autonomy. This would strengthen the Moscow-Damascus-Tehran hold on Syria but hey, that is where Trump’s heedless policy leads.

But Trump is not a normal president. He listens only to Fox TV talking heads and himself.

So the fate of the Kurds may turn on whether GOP senators — and even Fox commentators — warn the president that the blood of slain Kurdish allies would be on his hands and would forever blacken his image. That may be the only argument this president can understand.