The description “forever wars” is now associated with Iraq and Afghanistan, but the origins of the term are much older.

A quick database search unearthed a 1959 clip from the St. Louis Globe-Democrat about a convention of Esperanto speakers, who believed that a common worldwide language would end “forever wars.” And in 1974, Joe Haldeman, a Vietnam veteran, published an acclaimed science fiction novel, “The Forever War,” which was a parable drawn from Southeast Asia.

By 2008, New York Times correspondent Dexter Filkins popularized the label by calling his book on the never-ended struggles in Afghanistan, “The Forever War.”

But as the witty economist Herb Stein memorably said, “If something cannot go on forever, it will stop.” Fulfilling that dictum, Joe Biden decreed that America’s military involvement in the forever war in Afghanistan will stop by the tragic Sept. 11 anniversary.

The end was inevitable, despite the reported objections of leading generals and other national security officials. For what could the generals promise other than more of the same as the Taliban gains territory and shows scant interest in a power-sharing arrangement?

There certainly is no Afghan George Washington, even though nearly two decades ago, Hamid Karzai, the president installed by the George W. Bush administration, was briefly auditioned for the part. Even more unlikely is the emergence of an Afghan Ulysses S. Grant, with the courage and competence to end a military stalemate.

For all the inevitability, for all the lack of appealing options, the American withdrawal leaves me deeply saddened. This is a moral and emotional reaction, rather than one grounded in a strategic worldview.

Personal memories

But it is a mistake to underestimate soft values like altruism as a basis for U.S. foreign policy.

You don’t have to hold a Ph.D. in Cold War studies to be enraged by Vladimir Putin’s attempts to kill opposition leader Alexei Navalny. You don’t have to speak Mandarin to be horrified by China’s treatment of the Uyghurs or to lament the cynicism with which democracy was snuffed out in Hong Kong.

I make no claims to be an old Afghan hand or a terrorism expert. But I did spend a bit more than a week in Kabul during the heady days immediately after the Taliban had been routed, in December 2001. Memories from that brief visit shape my reaction to the impending American withdrawal.

I remember the ubiquitous powder blue burqas that nervous women still wore on the streets of Kabul — and the lightning speed with which my interpreter whipped off her head piece as soon as we stepped into an interior courtyard. Equally vivid is the morning I spent with a group of Afghan widows who proudly showed me where they operated a secret bakery to support their children under the Taliban.

An Afghan friend, whom I met in Kabul during that 2001 visit, succinctly explained the problems with many American aid efforts over the last two decades.

“Someone starts a project with the best of intentions,” he said, “and then he rotates home with the project half finished. His successor has a totally different idea and then he too goes home with that second effort uncompleted. And so it continues.”

That’s the tragedy of Afghanistan: There is no road map for success, but there’s a nearby exit ramp for failure.

It is easy to imagine the Taliban retaking control of Kabul and other holdout cities in a year or two. Equally plausible is another vicious civil war like the one that devastated Kabul in the early 1990s and paved the way for the Taliban.

Americans of the Vietnam era can recall the whirling helicopters taking off from the roof of the U.S. Embassy in Saigon as the North Vietnamese overwhelmed the city in 1975. Even more wrenching were the stories emerging from the Khmer Rouge takeover of Cambodia and the “killing fields” that followed.

That is what American retreat looks like. And the prayer is that this familiar story will not play out the same way in Afghanistan.

The right thing

What I am left with are words that seem naive and unfashionable in a world of suffering: There is a humanitarian case for remaining in Afghanistan to protect those who trusted us and believed that American power would bring them a better life, free from the religious fanaticism of the Taliban.

It is a variant on what Colin Powell during the run-up to the Iraq War called the Pottery Barn rule: “You break it, you’ve bought it.”

Yes, Afghanistan was broken when we arrived, and had been broken since the last king, Mohammad Zaher Shah, was ousted in a 1973 coup. But 20 years of uneven American involvement — military surges mixed with urges to withdraw — should bring with it moral obligations.

That sentiment does not fit with the “America First” blather from Donald Trump and his acolytes. Nor does it mesh with some grand global theory about the projection of American power in the 21st century.

But it is the right thing to do.

Maybe the right way to defend an ongoing involvement in Afghanistan would be to call it a “continued peace” instead of a “forever war.” Maybe the best idea is to let a generation of young Afghans grow up and aspire to more than survival in a brutal tribal society.

But I have no illusions about the future of our ever-shrinking involvement in Afghanistan. And that unavoidable truth is what makes the whole thing so sad.

Walter Shapiro has covered the last 11 presidential campaigns. He is also a fellow at the Brennan Center for Justice at NYU and a lecturer in political science at Yale. Follow him on Twitter @MrWalterShapiro.