In announcing a “permanent” cease-fire along the Turkish-Syrian border on Wednesday, President Trump smugly declared that “this was an outcome created by us, the United States, and nobody else.” The president, incapable of irony, was probably not referring to his own abrupt decision on Oct. 6 to stab Syrian Kurds in the back by giving Turkey a green light to attack them. Rather, he was giving credit to himself and to his vice president and secretary of state, who negotiated a partial cease-fire a week after President Recep Tayyip Erdogan of Turkey sent troops across the Syrian border to drive out Kurdish forces he considers a threat.

In Mr. Trump’s bizarre account, he claimed to have done Turkey and the Kurds a “great service” by creating a 20-mile-wide safe zone between them — “an interesting term, safe zone,” the president mused, as if he had just come up with a radically new concept. (The zone was in fact negotiated by Turkey and the Russians.) The president said he was lifting sanctions on Turkish products, and gushed that the commander of Kurdish forces “could not have been more thankful.”

Less than 24 hours later, that same Kurdish commander, Mazloum Abdi, was complaining on Twitter that Turkish forces were violating the “permanent” cease-fire brokered by Mr. Trump.

As is often the case with Trump pronouncements, it is hard to know where to begin. In effect, Mr. Trump was blithely taking full credit for ending a brutal battle he had a hand in starting and claiming a significant feat when in fact the betrayal of the Kurds and the brusque, thoughtless American withdrawal undermined American credibility and was a major victory for Presidents Vladimir Putin of Russia and Bashar al-Assad, the butcher of Syria.

There would have been no need to dispatch Vice President Mike Pence and Secretary of State Mike Pompeo to get a cease-fire had Mr. Trump himself not suddenly pulled American troops away from the border after a phone chat with Mr. Erdogan, the Turkish president and one of the strongmen rulers who melt the president’s heart. And Mr. Erdogan agreed to the cease-fire only after he effectively achieved everything he wanted, driving the Kurds far back from the Turkish border in a brief but murderous onslaught.

And only a day before Mr. Trump lifted sanctions on Turkey, Mr. Erdogan had spent several hours in Sochi, Russia, with a happy Mr. Putin — another of Mr. Trump’s paragons of effective governance — getting his marching orders from the Russian leader. With the Americans now out of the way and the Kurds in flight, Turkey and Russia will now jointly patrol the border area.

That Mr. Putin and Mr. al-Assad were now undisputed masters of Syria seemed not to faze Mr. Trump. Nor did he appear concerned that Turkey, a NATO ally whose country harbors American nuclear weapons, and whose leader recently let on that he is thinking of getting nukes of his own, was looking to buy state-of-the-art weaponry from NATO’s primary foe. “Other countries have stepped forward. They want to help, and we think that’s great,” Mr. Trump said, making clear that he meant not the European allies — who, as usual, got a passing whack from the back of the president’s hand — but rather Russian forces, recently accused in a Times investigative report of systematically bombing Syrian hospitals.

Perhaps it should not come as a surprise anymore that Mr. Trump sees anything he does as a great and unprecedented achievement, or that he views the Middle East as little more than a patch of “bloodstained sand” that Americans should stay out of, or that he puts more stock in dictators than in allies.

Yet it still comes as a shock that a man, already facing an impeachment inquiry over his misuse of the presidency to pressure Ukraine into doing his political dirty work, would not pause to wonder whether there might be a better way to conduct the foreign policy of the world’s most powerful — and once most respected — nation. In shaping his view on Ukraine, too, Mr. Trump apparently paid more heed to autocratic Ukraine-bashers like Mr. Putin and Prime Minister Viktor Orban of Hungary than to any of his own advisers.

At times, Mr. Trump’s televised statement seemed almost like a “Saturday Night Live” parody with lines like, “We’ve done something that’s very, very special,” or, “It’s too early to me to be congratulated.” All the while, Mr. Pence, Mr. Pompeo and the national security adviser, Robert O’Brien, gazed at the president with blank expressions. It’s hard to believe they were not anxiously trying to guess what “very special” fire they’d next be sent to fight.