The nation should be alarmed by the seeming instability and impulsive actions of its president.

After a Sunday conversation with President Recep Tayyip Erdogan of Turkey, a strongman who has sought to consolidate power and trampled on rights when he found them inconvenient, President Donald Trump announced a major and troubling shift in U.S. policy.

“Turkey will soon be moving forward with its long-planned operation in Northern Syria,” read a White House statement released at 11 Sunday night. “And United States forces,” the statement concluded, “having defeated the ISIS territorial ‘Caliphate,’ will no longer be in the immediate area.”

It adds up to this — America will stand aside as Turkey attacks Kurdish forces along its border in Syria.

Finding the opportunity to strike the Kurds is what Turkey’s “long-planned operation in Northern Syria” has always been about. On Tuesday, Erdogan told reporters the Turkish military forces were massing on its border and an attack on the Kurds was imminent.

That has not happened up until now because of the presence of about 1,000 U.S. military personnel alongside the Kurds. It was Kurdish fighters, part of the Syrian Democratic Forces and supported by U.S. air support and military intelligence, who were the point of the spear in driving the Islamic State from Syria in often brutal building-to-building urban fighting. The SDF suffered 11,000 fighters killed, the bulk of them Kurds.

Abandoning this ally to a potential slaughter by a much stronger opponent is morally wrong. It also happens to be a terrible foreign policy and military decision. This small footprint of American military personnel has prevented a Turkish-Kurdish war that would further destabilize the region; discouraged the reformation of the Islamic State in Syria; and served as a check on further Russian expansion and influence.

Most alarmingly, Trump made this decision on the advice of a foreign leader but without consulting the generals at the Pentagon or the diplomats at the State Department. If the decision stands, it will send the unmistakable message that the United States cannot be a trusted ally once the fight is over. Good luck forming regional alliances when future global conflicts emerge.

And this rash decision could well lead to a resurgence of ISIS in the region. The Kurdish forces are guarding thousands of Islamic State fighters in makeshift prisons in the territory, a task they could well abandon if soldiers must turn their attention to a fight with Turkey.

Erdogan sees the Kurdish forces as a threat to Turkey, with their successes on the Syrian side of the border making Kurds in his country more emboldened about their aspirations for a homeland and self-rule. The Turkish strongman also needs a victory after recent domestic political defeats.

This should sound familiar. Last December Trump announced plans for a complete withdrawal from Syria — we didn’t like it then, either — only to face strong pushback from within his administration. While the size of the U.S. footprint was reduced, the military presence continued. Now, however, the guardrails are gone, with those individuals who would have challenged the president on such a rash move having left the administration in one manner or another.

Maybe the president will respond to the fact some of his biggest apologists in the Republican Party — folks such as Senate Majority Leader Mitch McConnell of Kentucky and Lindsey Graham of South Carolina — are not standing behind him on this move.

"By abandoning the Kurds we have sent the most dangerous signal possible — America is an unreliable ally and it's just a matter of time before China, Russia, Iran, and North Korea act out in dangerous ways," tweeted Graham.

Trump could again reverse course. He should. The president can always deny having ever made the decision in the first place. Creating his own alternative reality is what Trump does.

But even in attempting to provide reassurance, Trump only raised more questions about his fitness to serve, describing himself in narcissistic terms that would make even a dictator blush, then offering a bizarre threat.

“As I have stated strongly before, and just to reiterate, if Turkey does anything that I, in my great and unmatched wisdom, consider to be off limits, I will totally destroy and obliterate the Economy of Turkey (I’ve done before!),” tweeted the president.

Where have we heard that? Oh, the movie. “I am the great and powerful Wizard of Oz.”

If only we could ignore the man behind this curtain.

The Day editorial board meets with political, business and community leaders to formulate editorial viewpoints. It is composed of President and Publisher Timothy Dwyer, Executive Editor Izaskun E. Larraneta, Owen Poole, copy editor, and Lisa McGinley, retired deputy managing editor. The board operates independently from The Day newsroom.