Fighters from the Syrian Democratic Forces stand near the destroyed Uwais al-Qarni shrine in Raqqa, Syria.Rodi Said / Reuters

Nothing in the presidency of Donald Trump combines tragedy and farce so perfectly as his decision to withdraw the 2,000 American troops in Syria.

“We have defeated ISIS in Syria, my only reason for being there during the Trump Presidency,” he tweeted on the morning of December 19. The claim was false on its face. The Islamic State has lost most of its territory, but it retains thousands of fighters in the desert where the Euphrates River crosses from Syria to Iraq. Those fighters could be more dangerous as insurgents and terrorists than as the territorial army of a self-proclaimed caliphate.

Trump’s announcement was so ill-considered and rushed that it blindsided his most important advisers, prompting the resignations of Defense Secretary James Mattis and Brett McGurk, special envoy to the anti-ISIS coalition. Diplomats and aid workers involved in rebuilding liberated Syrian towns were given 24 hours to evacuate the country. U.S. Special Forces now have to abandon the training of the American-allied, Kurdish-led Syrian Democratic Forces, a job that General Joseph Dunford, the chairman of the Joint Chiefs, recently said was only 20 percent finished. For American troops dedicated to the ethic of leaving no friend behind on the battlefield, Trump’s order has to be particularly bitter.

The Syrian Democratic Forces were the only local army capable of beating the Islamic State, and in pushing ISIS out of its strongholds—including the caliphate’s capital, Raqqa—the Syrian Kurds paid a heavy price. America will now leave them to their fate. Turkey considers the People’s Protection Force, or YPG, to be terrorists indistinguishable from the Kurdish Workers’ Party in Turkey, and nothing now prevents the Turkish army from a murderous attack on the Syrian Kurds. In a phone call four days before Trump’s decision, Recep Tayyip Erdogan, Turkey’s autocratic president, played him perfectly, flattering Trump by telling him that, with ISIS defeated, Turkey could take it from here—so why would America stick around for the Kurds? “You know what?” Trump reportedly said. “It’s yours. I’m leaving.” It’s yours—do what you want with it. Now that he’s rid himself of every U.S. official willing to tell him what he doesn’t want to hear, Trump can turn for policy advice to foreign dictators.

The American troops in Syria were never easy to explain. Since a final victory over the Islamic State isn’t possible, what was our goal? Not to end the Syrian civil war—that has never been a serious American aim, since it would require a military and diplomatic commitment that American voters and their elected leaders have no interest in making. The most that Americans have tried to achieve in Syria is to mitigate the worst—to deter Bashar al-Assad from gassing his own people, to stabilize areas occupied by the Syrian Democratic Forces, to counteract Russian and Iranian influence, to keep the Islamic State on the run, to prevent Turkey from slaughtering the Kurds. Those goals suggested an American presence, however small, without end.

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Trump looked out across this unsatisfying landscape and saw another way, one more in tune with his own psychic needs, and perhaps with the real desires of most Americans: Declare victory and get out. Claim credit for both the win and the withdrawal. When our enemies return and our friends are wiped out—for not even Trump can believe that this is unlikely—find someone else to blame.

There’s a history behind Trump’s sudden decision. In the face of a war that offers no prospect of complete victory, or any victory, the temptation to betray an ally and call it success has seduced far more serious presidents than Trump. The historical pattern is instructive, and so is the fact that, this time, there’s a difference.

By 1969, the Vietnam War was lost. Instead of telling the American people this hard truth, the new president, Richard Nixon, and his national-security adviser, Henry Kissinger, spent four more years in pursuit of what Nixon called “peace with honor.” He wanted to find a way out of Vietnam that wouldn’t hurt his reelection chances or his broader foreign policy. He wanted to be able to say that 58,000 Americans did not die in vain.

At the same time, Nixon and Kissinger were well aware that peace with honor wasn’t possible—an American withdrawal would mean the end of South Vietnam.

Kissinger’s solution was a deal that would leave the Saigon government in place long enough for the world to blame the South Vietnamese for their own inevitable downfall. “If a year or two years from now North Vietnam gobbles up South Vietnam, we can have a viable foreign policy if it looks as if it’s the result of South Vietnamese incompetence,” Kissinger told Nixon in August 1972, during peace talks with the North Vietnamese. “So we’ve got to find some formula that holds the thing together for a year or two, after which—after a year, Mr. President, Vietnam will be a backwater. If we settle it, say, this October, by January ’74 no one will give a damn.” Kissinger called this scheme “a decent interval.”

On January 23, 1973, after 12 years of Americans fighting and dying in Vietnam, Nixon announced the end of the war in a nationally televised speech that was full of lies. He said that the peace to be signed in Paris “has the full support of President Thieu and the government of the Republic of Vietnam”—our South Vietnamese ally. In fact, Thieu had to be coerced and deceived into accepting the deal with threats and false promises. Nixon told the country, “Let us be proud that America did not settle for a peace that would have betrayed our allies, that would have abandoned our prisoners of war, or that would have ended the war for us but would have continued the war for the 50 million people of Indochina.” The people of Indochina enjoyed barely a day of peace before the fighting resumed, as both North and South Vietnam predictably broke the cease-fire. By keeping North Vietnamese troops in the South and Nguyen Van Thieu in power, the Paris Peace Accords guaranteed that the war would go on, without the Americans.

The cynicism of the decent interval—the deception and self-deception—ensured that the denouement in Vietnam would be cataclysmic. In April 1975, the Ford administration was unprepared to evacuate those Vietnamese partners of America whose lives were directly threatened by a communist takeover. But Kissinger was right: When the end came, not many Americans gave a damn. Congressional Democrats, who viewed any appropriations for Vietnam as wasteful efforts to prolong the war, refused to authorize money to save desperate people. The public, wanting to be rid of the nightmarish memory of the war, paid little attention. Only the heroic actions of individual Americans in South Vietnam, often working against official orders, rescued thousands of Vietnamese men, women, and children. Far more were left behind. (This story is the subject of a powerful new book, Honorable Exit, by Thurston Clarke.)

Barack Obama, born the year the American war in Vietnam began, became the next president faced with the elusive search for peace with honor. He opposed the war in Iraq as an Illinois state senator, and he was vindicated when the occupation produced a lethal insurgency, a civil war, thousands of American and hundreds of thousands of Iraqi deaths, and a terrorist group called al-Qaeda in Mesopotamia. In 2008, Obama campaigned on a promise to withdraw American troops. At the beginning of his presidency, he announced that the combat mission in Iraq would end on August 31, 2010. And when that day arrived, he declared success:

Ending this war is not only in Iraq’s interest—it’s in our own. The United States has paid a huge price to put the future of Iraq in the hands of its people. We have sent our young men and women to make enormous sacrifices in Iraq, and spent vast resources abroad at a time of tight budgets at home. We’ve persevered because of a belief we share with the Iraqi people—a belief that out of the ashes of war, a new beginning could be born in this cradle of civilization. Through this remarkable chapter in the history of the United States and Iraq, we have met our responsibility. Now it’s time to turn the page.

It would have been beyond any president’s capacity for bitter candor to say instead: “Iraq has no functioning government. The political class is incapable of compromise. Our chosen partner, Prime Minister Maliki, is thoroughly corrupt and sectarian. After seven years of this war, ordinary Iraqis still live without reliable services or security. We will leave behind a power vacuum that will be filled by Shiite pawns of Iran and Sunni extremists. At some point, Iraqi cities that our troops fought to clear will probably fall again to our enemies. Iraqis being hunted down for their association with us are on their own. We haven’t come close to meeting our responsibilities. But we’re tired, we have our own problems, and so this artificial date I set 18 months ago will have to do as an ending.”

In both Vietnam and Iraq, ending the war wasn’t the wrong policy. The wrong lay in Nixon’s cynically prolonging a lost war for four years, and in Obama’s failure to anticipate the return of chaos in Iraq. The wrong was to pretend that those wars were something other than historic disasters that could never be made right, and to shift our blame to others. If peace with honor is impossible, better to be honest about that fact than to allow an illusion to drift into a catastrophe.

Syria is neither Vietnam nor Iraq. Those 2,000 American troops weren’t an expression of imperial arrogance or blind doctrine. Obama sent them in 2014 with great reluctance, despite his long-standing fear of being drawn into a complex, multisided quagmire. The precipitating event was the threatened genocide of Iraqi Yazidis by murderers from the Islamic State, who killed and enslaved enough to make the threat credible. The Yazidis who survived as refugees—many of whom were later able to return to their homes—owe their lives at least in part to Obama’s intervention. Anyone who opposed it would have been answerable for a great crime against humanity, just as those who supported it are answerable for the thousands of civilians killed by American bombs in the push to free Mosul and Raqqa from the Islamic State. None of us gets off.

There were reasonable arguments for staying out of Syria, including the lack of any congressional or public debate. It would have been much better for Congress to have authorized the use of force—but the Republican majority washed its hands of the matter. In our hyper-partisan time, foreign policy itself would be just about impossible if it depended on Congress. Nor did congressional authorizations in Vietnam and Iraq ensure either a wise policy or public support.

In four years, four Americans have been killed in Operation Inherent Resolve. The lightness of American casualties has partly contributed to heavy civilian deaths—at least 1,400 in Raqqa—because keeping fewer boots on the ground means greater reliance on air power, which is less discriminating. On the whole, though, U.S. support for the Syrian Democratic Forces—made up of Arabs as well as Kurds—has gained a significant, if slow and painful, return on a small investment. For the first time, there’s a decent fighting force in Syria, a margin of hope between Assad’s barrel bombs and the Islamic State’s bloodlust. Any theory of international relations that looks with indifference on its elimination, and prefers a three-way fight among Erdogan, Assad, and ISIS, shouldn’t be called realist.

This time, an American withdrawal will not have been preceded by years of sunk blood and treasure—just by the president’s lust for bragging rights and his indifference to any cause greater than some chimerical “win.” Trump’s version of peace with honor—like so much about his presidency—is notable for its blatant stupidity, its needless cruelty. Everyone, even the Trump mouthpieces on Fox News, knows that the Islamic State isn’t “defeated.” The betrayal of our Kurdish and Arab allies is entirely gratuitous. They will pay the price; we will soon forget. There will be no peace for them and no honor for us.