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By Jonathan Rauch

Imagine owning stock in a company that goes bankrupt. Holding a fistful of worthless shares, you feel regretful, dismayed, even angry. All that money … lost. What a mistake! What a failure!

But wait. Suppose you had bought the stock 20 years ago and it paid dividends every year. Those dividends helped cover your family’s mortgage and put your kids through school. Doesn’t that cast a different light on the matter? Despite the disappointing ending, you can feel pretty good about your investment.

This is the calculus America is facing in assessing its 20-year stabilization campaign in Afghanistan. Abruptly, though not entirely unexpectedly, the Biden administration is pulling out. No one knows what will happen next, but most analysts expect the Taliban to tighten its grip on the countryside and perhaps conquer the whole country—possibly without much of a fight. Emboldened, the Taliban have been pressing forward aggressively and made some significant gains.

Conventional wisdom sees another in a string of lost U.S. wars. “America’s war in Afghanistan is ending in crushing defeat,” headlines The Economist. The U.S. is “calling an end to the whole sorry adventure, with almost nothing to show for it,” the magazine editorializes. In Foreign Policy magazine, Emran Feroz writes, “The war began as it is ending, in failure.” A headline in the same publication says “Afghanistan Is America’s Greatest Strategic Disaster.” Those are only a few random examples of countless declarations of defeat.

Well, hold on a minute. Humility cautions us not to be confident of how Afghanistan will look in five or ten years. But let’s assume, for argument’s sake, that the Taliban do retake power and resume their campaign to make Afghanistan medieval again. Assume a refugee crisis, human rights violations, and even resumption of terrorist activity. Yes, that would be bad. Yes, history—and, possibly, American voters—would judge President Biden harshly for it.

But it would not have made the campaign a mistake—or even, on its own terms, a failure. To the contrary: Even assuming the worst, the operation should be considered at least a partial success and well worth the effort—flawed and limited, to be sure, but better than the alternatives and far from a strategic or moral catastrophe.

To begin with, the financial cost (something in the $1 trillion to $2 trillion range) was substantial but, over 20 years, quite sustainable. “Given the size and scale of our military, and what we spend on it, I don’t think Afghanistan amounted to all that much in the end,” Jacob Heilbrunn, the editor of The National Interest magazine, told me recently.

The cost in U.S. fatalities was too high in the sense that any fatalities are too many; but, as long wars go, this one’s total was modest: about 2,500 U.S. military fatalities, versus almost twice that total in Iraq and, of course, far more (upwards of 58,000) in Vietnam. Moreover, since 2015, after the U.S. ended its surge and delegated front-line fighting to the Afghans, annual U.S. fatalities have not risen above two dozen. More service members die every year in training accidents. (In fact, the relatively low fatality numbers are a reason to be puzzled that President Biden felt such urgency in pulling out.)

As for the Afghans, they assuredly suffered in the war, but they suffered more under Taliban rule. Michael O’Hanlon of the Brookings Institution figures that the war may have cost 400,000 Afghan lives over the past 20 years, but he guesstimates that U.S. activities there saved a million or more lives, a significant net positive.

Consider: Infant mortality dropped by half during the U.S. operation. Life expectancy improved by six years. Electricity consumption, a key quality of life indicator, increased by a factor of 10. Years in school increased by at least three years for men and four for women. University graduates rose from under 31,000 to almost 200,000. (Those and other indicators are available at the Brookings Afghanistan index.)

Those are a lot of lives saved and improved. Even at their most monstrous, the Taliban cannot roll back all the gains of the past 20 years. In fact, back in power, they would find a different country than the one they left: one with a substantial Western-educated elite and a population that has known peace and progress. “That’s what’s going to challenge the Taliban or anyone who comes in to take over leadership,” Shuja Rabbani, an Afghan expatriate and son of a former president, told me. “They’re going to have a very different kind of fight to put up.”

Those gains would count for less if they had come at a major strategic cost—as was the case in Iraq, where the deposition of Saddam Hussein cleared a path for Iran’s domination of the region. But none of the people I spoke to for this article cited any comparable strategic cost in Afghanistan. No American adversary was strengthened; to the contrary, ambitions of rivals like Iran, Pakistan, China, and Russia were blocked. No allies were alienated; to the contrary, four dozen countries had joined the campaign by 2014, and 36 countries, from Albania to Ukraine, were still contributing forces as of February, according to NATO. If anything, the operation strengthened NATO and America’s alliances. “It was remarkable how much the NATO coalition held throughout this thing,” O’Hanlon said.

All of that is before reckoning the Big Payoff, which is not what you see but what you don’t see: For 20 years, there has been no major attack on the U.S. homeland.

When President George W. Bush launched the attack on the Taliban, the aim he announced was to “disrupt the use of Afghanistan as a terrorist base of operations, and to attack the military capability of the Taliban regime.” That aim was accomplished. Bases, soldiers on the ground, copious intelligence, and a friendly government allowed the U.S. to effectively incapacitate al-Qaida & Co. “Afghanistan is where the [terrorist] center of gravity was,” O’Hanlon said. “I think you have to say that the safety of the homeland since 9/11 is largely a byproduct of the Afghanistan mission. You have to count the fact that we haven’t been attacked again since 9/11 in any major way on U.S. soil as a huge success.”

If you had told me on September 12, 2001, that there would be zero major attacks on U.S. soil for 20 years, I would have had you drug-tested. Even if the Taliban were to revert to harboring terrorism, 20 years of security was no waste of time.

Remember, all of that is assuming the worst. It is possible that the Afghan government will hold on to part of the country and force an entente; that, even if they take over, the Taliban, now under different leadership and leading a changed country, will govern less toxically; that, even if they govern just as toxically, they will not risk harboring terrorists and drawing American forces back in. No one who watched communist forces take over Vietnam in 1975—a seeming cataclysm at the time—imagined that the government there would overthrow a genocidal regime in Cambodia, modernize the economy, normalize relations with the U.S., and welcome a former POW back for friendly visits.

For all of those reasons, I am resolutely agnostic on Biden’s withdrawal decision. Anyone who thinks the answer is obvious hasn’t thought seriously about it. Given the many imponderables and unpredictables on both sides of the equation, the intuitions of the president and the public may be a better guide than any stack of white papers.

Regardless, consigning Afghanistan to the “lost wars” category is a mistake. Even if withdrawal brings chaos, that does not mean the operation was a failure. Decisive triumphs like victory in the Cold War are grand but rare; more often, liberal countries succeed by muddling through, temporizing, and preventing the worst rather than achieving the best. In Afghanistan, the U.S. did not achieve the best, but a generation-long dividend of security, stability, and decency is something to appreciate and learn from, not something to condemn and dismiss.

Jonathan Rauch is a columnist at Persuasion and the author of The Constitution of Knowledge: A Defense of Truth.