Last week brought the 35th quarterly report from the indefatigable John Sopko about your investment in Afghanistan. It’s kind of like having the Grim Reaper as a houseguest. Repeatedly.

Much of Afghanistan, the Special Inspector General for Afghanistan Reconstruction told Congress, remains under the control of the Taliban, which the U.S. drove out of the capital of Kabul nearly 16 years ago. The continuing war, as the Taliban attempts to claw their way back into power, is generating a “shockingly high” number of dead Afghan troops and record civilian casualties, he added in a report made even more depressing because so little attention has been paid to it.

“America’s longest war is now in its sixteenth year, driven by the long-standing goal of ensuring that Afghanistan never again serves as a platform for terrorist attacks on the United States,” Sopko said in his 273-page tome. “The fighting continues, as does a reconstruction effort that has so far absorbed more than $117 billion in congressional appropriations. Both the security and civil aspects of reconstruction—ranging from developing Afghan security forces and advising ministry staff, to building clinics and electrifying towns—have yielded mixed results.”

“Mixed results” is Sopko’s delicate way of describing where the U.S. finds itself: “A dangerous and stubborn insurgency controls or exerts influence over areas holding about a third of the Afghan population. Heavy casualties and capability gaps limit the effectiveness of Afghan soldiers and police. Opium production stands near record levels. Illiteracy and poverty remain widespread. Corruption reaches into every aspect of national life. The rule of law has limited reach. Multiple obstacles deter investors and complicate business operations. The ranks of the job-less grow as the economy stagnates.”

When I first visited Afghanistan, it was six months after the U.S. arrived. There was a sense of optimism on that trip to Bagram, Herat, Kabul and Mazar-e-Sharif that faded on subsequent visits. Increasingly, the country seems like a sick man on life support, kept only alive by a steady infusion of U.S. dollars and troops.

The U.S. invaded Afghanistan on Oct. 7, 2001, to destroy the Taliban government for sheltering Osama bin Laden’s al Qaeda, responsible for the attacks of 9/11 26 days earlier.

That was 5,692 days ago. And nearly $1 trillion and 2,185 U.S. troops’ lives ago. What kind of a nation tolerates such a long-sucking chest wound? A raw recruit deployed to the Afghan campaign in its opening days is now thinking about retirement. What kind of military willingly walks onto a perpetual treadmill when the chance of prevailing is next to nil? What does that tell us about our leaders? More critically, what does it say about us, the led?

“You have the watches,” a captured Taliban fighter supposedly said more than a decade ago, “but we have the time.” A Viet Cong could have said the same thing in 1967.

“After sweeping the Taliban from Kabul with a dramatic campaign, the mighty United States remains stuck in Afghanistan,” Ehsan M. Ahrari of the Army War College wrote last Wednesday. “…there is no likely victory for the American military in Afghanistan. The country offers a grim and uneasy choice – lose now or later.”

President Obama, after doubling down on a war he inherited, strived mightily to bring the troops home. But the Taliban refused to cooperate. Now U.S. commanders say they want up to 5,000 more American troops—a 60% boost over the 8,400 now there—to aid their Afghan allies. The effort would cost an estimated $23 billion annually, eclipsing Afghanistan’s annual GDP. In fact, according to a recent accounting by the independent Costs of War project at Brown University, the money spent by Americans fighting in Afghanistan will top that spent in Iraq sometime this year.

President Trump, unlike Obama, is unwilling to set (oft-ignored) deadlines for U.S. troops to withdraw. Bottom line: There is no end in sight to this war. “Even if the president increased the number of troops there, the war would only be lost at a higher cost,” says Daniel Davis, a retired Army officer and Straus Military Reform Military Advisory Board Member who spent two tours in Afghanistan.

Mark my words: it will eventually end, as it did in Vietnam, with a fig-leaf withdrawal followed by the tides of history, which will wash away, within a decade, any evidence of our presence.

It’s time to acknowledge the truth. We can’t rebuild Afghanistan. But we can keep it from becoming petri dishes for terror, as we are now doing in Somalia and Yemen, with commandos and drone strikes. That is the only sustainable path forward.

Ocean-hopping non-state terrorists are going to be with us for much of the 21st Century. They are going to be fueled by globalization, inequality in money and natural resources, and religious zealotry. Neither the U.S. nor any other nation, nor any combination thereof, can defeat such small and dedicated violent ideologues, in the traditional military sense. They exist as much in cyberspace as they do in physical space.

The 9/11 terrorists hurt America, and killed nearly 3,000 people, because they harnessed our airplanes against our buildings. We have done a much better job of keeping our weapons out of their hands since then. That must remain our priority, especially in the case of nuclear arms, the only true weapon of mass destruction.

Like the automobile crashes and opioid addictions that kill about 50,000 Americans every year—that’s 1,000 a week—terrorism is largely a modern scourge. After all, one can’t terrorize without modern communications to broadcast the slaughter. It generates a fear all out of proportion to the number it kills because, unlike car crashes, terrorism is no “accident,” nor is an unfortunate side effect of modern medicine.

But our reaction needs to be tempered by reality. Are we consigned to a perpetual war on terror? It sure looks that way, given the yardstick the U.S. has been using to assess progress in Afghanistan.

Sopko’s too much of a diplomat to say so, but it’s time to stop pretending we can prevail according to our own dated metrics. Yet he does have some good advice. “With a new Administration and a new Congress, it is a good idea and opportune time to reevaluate our efforts in Afghanistan and find out what’s working,” he concludes, “and what’s not.”