It is a cliché to say that certain eras "end not with a bang, but a whimper," but the old trope is true in Afghanistan. U.S. and Taliban officials signed an agreement over the weekend that should lead to the withdrawal of American troops from that country — a development mostly overshadowed by the spread of coronavirus and developments in domestic presidential politics.

That shouldn't be the case. Attention must be paid. Along with the war in Iraq, the Afghan experience defines the U.S. interactions in the world in the 21st century — a righteous display of might that ultimately devolved into an unending, unsolvable, exhausting slog.

The war began on 9/11, when hijackers flew passenger planes into the World Trade Center and the Pentagon — another plane crashed in the Pennsylvania countryside — killing 2,977 victims and 19 hijackers. More than 2,300 American servicemembers have died in Afghanistan over the last generation, while estimates say that 157,000 people died there during the war — including more than 43,000 civilians. Everything about the war has been a tragedy.

The invasion of Afghanistan is the only U.S. military offensive that I have wholeheartedly rooted for during my adult life. A few weeks after 9/11, I drove from my home in Kansas to New York — via the Flight 93 crash site in Pennsylvania — to witness history for myself. Smoke was still wafting from the bowels of the Twin Towers. Like Americans everywhere, I wanted revenge.

I didn't believe for one second that the Al Qaeda terrorists hated us "for our freedom," the easy explanation offered Americans during the early days of "why do they hate us?" questioning after the attack. But thousands of civilians had been killed — in the first days after 9/11, it was widely believed that tens of thousands of civilians had been killed — and in the heat of the moment, it seemed that such massive violence must be met with equally massive violence. When Vice President Dick Cheney went on TV the next weekend to hint at the likelihood of torture in the coming conflict — promising U.S. personnel would work on "the dark side, if you will" — even that seemed to make sense to a nominal pacifist like myself.

I was wrong. We — all of us who cheered the invasion and occupation of Afghanistan — were wrong.

We were wrong because we ignored world history. There was a reason that Afghanistan — occupied over the years by the British, then by the Soviets — was already known as "the graveyard of empires." For cultural and geographic reasons, no would-be conqueror of the country has ever fully subdued its people. Responding to the 9/11 attack was not necessarily America's big mistake. Staying and trying to recreate Afghanistan in something like our own image was the crucial error, both hubristic and well-intentioned — we thought we could be the conquerors who left the country better than we found it. We are not.

We were wrong, too, because we ignored our own history. By the time 2001 arrived, the memories of America's misadventures in Vietnam had mostly faded, pushed down the memory hole by the end of the Cold War and U.S. battle victories over a series of weaker foes, including Iraq during the first Gulf War in 1991. The military establishment turned its attention in the late 1970s and 1980s to the task of confronting the Soviet Union, forgetting whatever it had learned about counterinsurgency wars. America's leaders were prepared for tank battles and seizing capitals — and were less ready to deal with guerilla warfare. The tactical lessons of Vietnam might have helped had they been implemented earlier, but Americans also ignored the bigger strategic lesson: that it doesn't ultimately serve U.S. interests to get bogged down, thousands of miles from home, fighting rebel guerillas on their own land. We're bad at it.

We were wrong, finally, because the real enemy — the stateless terrorists of Al Qaeda — were not the opponents we wanted or were prepared to fight. When Pearl Harbor happened, the United States conquered Japan. When the USS Maine sunk in Havana Harbor, Americans went to war with Spain and ended up governing Cuba and the Philippines. Al Qaeda terrorists roamed from Saudi Arabia to Germany to, yes, training camps in Afghanistan in preparing for the 9/11 attacks. But there was no chance the United States was going to invade Riyadh or occupy Hamburg. We invaded and occupied Afghanistan because 9/11 felt like war, so we responded like we always do in war — we took over somebody else's land. And then, for good measure, we stupidly went and did the same thing in Iraq.

That was never the wisest strategy against Al Qaeda, which could melt away from the battlefield and reorganize somewhere else. Indeed, Osama bin Laden wasn't brought to justice for nearly a decade — he was hiding out in Pakistan when U.S. troops found and assassinated him. American forces have remained in Afghanistan since then, fighting and dying for nearly another decade.

It has long been clear that it is time for America to cut losses and come home. Most U.S. veterans say the fight hasn't been worth it. Me? I no longer want revenge — not when it comes at the costs of more dead and injured, not when so many of the new dead and injured weren't even born when 9/11 occurred.

But we should not fool ourselves. The end of American involvement in Afghanistan will not mean the end of that country's civil war. There are probably calamitous days ahead for the people of Afghanistan. That is to be deeply lamented, but there is not much the United States can do to solve that problem. The tragedy there will continue. After a generation of losses, the least-bad thing we can do is end our role in it.

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