Two decades after invading Afghanistan, the United States is withdrawing, leaving chaos in its wake and the country much as it found it 20 years ago. “The Taliban don’t just control Kabul, but the whole country.” How did a war that began in response to the 9/11 attacks become the longest in American history? “If somebody had told me in 2001 that we were going to be there for another 20 years, I would not have believed them.” And what lessons can be learned for the future? “We were doing the same thing year after year after year, expecting a different result.” “Nearly 2,400 Americans have died in Afghanistan.” “More than 43,000 Afghan civilians lost their lives.” “You can’t remake a country on the American image. You can’t win if you’re fighting people who are fighting for their own villages and their own territory. Those were lessons we thought we learned in Vietnam. And yet, 30, 40 years later, we end up in Afghanistan, repeating the same mistakes.” On the morning of Sept. 11, 2001, President George W. Bush was visiting an elementary school in Sarasota, Fla., when he received word of an attack on the World Trade Center in New York City. “We’re looking at a live picture of the, of the building right now. And, uh, what would you say? That would be about the 90th floor or so?” The president joined his staff in an empty classroom, where his C.I.A. intelligence briefer, Michael Morell, had been watching the attack unfold. “There was a TV there and the second plane hit.” “Oh my goodness.” “Oh God.” “There’s another one.” “Oh.” “Oh my goodness, there’s another one.” “God.” “And when that happened, I knew that this was an act of terrorism.” At the Capitol in Washington, Representative Barbara Lee’s meeting was interrupted. “I heard a lot of noise saying, ‘Evacuate. Leave. Get out of here. Run fast.’ So, I ran up Independence Avenue. As I turned around, I was able to see a heck of a lot of smoke.” “Another aircraft, unbelievably, has crashed into the Pentagon.” “What you have to understand is this is the largest attack ever in the entire history of the country.” At 9:59 a.m., the second World Trade Center tower to be struck collapsed. Twenty-nine minutes later, the other tower followed. “The president, he asked to see me in his office on Air Force One. The president looked me in the eye and he said, ‘Michael, who did this?’ I told the president that I would bet my children’s future that Al Qaeda was responsible for this attack.” Within hours, evidence surfaced that Al Qaeda, a multinational terrorist organization headed by the Islamic fundamentalist Osama Bin Laden, had committed the attacks. The group was being given safe haven in Afghanistan by the Taliban regime. “The president’s inclination was to hit back and hit back hard.” “I can hear you. The rest of the world hears you. And the people — ” “So the president decided to go to war.” “ — And the people who knocked these buildings down will hear all of us soon.” “We had to go to Afghanistan. There’s no question in any of our minds, it’s a war of necessity. We had to go after Al Qaeda, we had to kill them, we had to get them out, and we had to pursue them to the ends of the earth.” “The word on the street was everyone’s got to be united with the president. You know, the country is in mourning.” Three days after the attacks, Lee was under pressure to vote yes on a resolution in Congress to authorize going to war against Al Qaeda and its allies when she heard a eulogy at a memorial service. “That as we act, we not become the evil we deplore.” “It was at that point I said, We need to think through our military response, our national security response and the possible impact on civilians.” “Mr. Speaker, members, I rise today really with a very heavy heart. One that is filled with sorrow for the families and the loved ones who were killed and injured this week. Yet I am convinced that military action will not prevent further acts of international terrorism against the United States.” “Got back to the office and all hell was breaking loose.” “The only dissenting voice was Democrat Barbara Lee of California, voting no.” “Phone calls, threats. People were calling me a traitor. She’s got to go. But I knew then it was going to set the stage for perpetual war.” Within weeks of 9/11, the U.S. struck back in Afghanistan. “The United States military has begun strikes against Al Qaeda terrorist training camps and military installations of the Taliban regime.” Soon after, U.S. ground troops arrived in the country. “The invasion was a success very quickly.” “At the gates of Kabul, news of a Taliban collapse had already reached these thousands.” “The Taliban retreat has turned into a rout.” “By the end of the year, the Taliban had been driven from power. A large number of Al Qaeda operatives had either been killed or captured.” And although Osama Bin Laden had managed to escape, the U.S. had accomplished its main goal. “Al Qaeda could not operate out of Afghanistan anymore.” President Bush knew there was a history of failed military campaigns in Afghanistan. “We know this from not only intelligence but from the history of military conflict in Afghanistan. It’s been one of initial success followed by long years of floundering and ultimate failure. We’re not going to repeat that mistake.” [Applause] But after his initial success, Bush expanded the mission to nation-building. To prevent further Al Qaeda attacks, his administration said it wanted to transform the poor, war-torn country into a stable democracy, with a strong central government and U.S.-trained military. “The idea was it would be impossible for the Taliban to ever return to power and impossible for Afghanistan to ever be used as a safe haven again.” “There were girls starting to go to school, there were clinics and hospitals being set up, there were vaccinations, there were elections planned. Everything was kind of humming along and we all thought, OK, this is going to be fine.” But by the mid-2000s, after the Bush administration expanded the war on terror to Iraq, Richard Boucher realized that the U.S.-backed Afghan government was plagued by corruption and mismanagement. “I used to say to my guys on the Afghan desk, ‘If we’re winning, how come it don’t look like we’re winning?’” “The Taliban have staged a major comeback, seizing control of large swaths of the country.” “The people were not rejecting the Taliban. And that was, in the end, because the government couldn’t deliver much for the people. Everybody had this idea in their heads that government works the way it does in Washington. But Afghanistan hasn’t worked that way in the past. I think that was a moment we should’ve at least asked ourselves whether it wasn’t really time for us to leave and to say to the Afghans, ‘It’s your place, you run it as best you can.’” Instead, by 2011, President Bush’s successor, Barack Obama, had sent nearly 50,000 more troops to Afghanistan, hoping to reverse the Taliban’s gains. “I think one of the biggest mistakes we made strategically, after 9/11, was to fail to finish the job here, focus our attention here. We got distracted by Iraq.” One of those troops was Marine Captain Timothy Kudo. Part of his job was to shore up support for the government by digging wells and building schools. He soon lost faith in that mission after, he says, his company killed two Afghan teenagers they mistakenly believed were firing on them. “And their family saw this happen. The mothers, the grandmothers, they came out. It was the first time I’d ever seen an Afghan woman without wearing a burqa. They were sobbing and crying uncontrollably. I mean, how can you kill two innocent people and expect anything that you say to matter at that point?” “People here have little faith in U.S. forces anymore. More Afghans now blame the violence here on the U.S. than on the Taliban.” Weeks after Kudo returned home from Afghanistan, there was a monumental development. “I started getting all these texts, like, ‘You’ve got to check out the TV.’ My roommate calls me from the other room. ‘Turn on CNN.’” “The United States has conducted an operation that killed Osama Bin Laden, the leader of Al Qaeda.” “U.S.A.! U.S.A.!” “In that moment, people are celebrating in front of the White House. They’re celebrating by Ground Zero.” “This is where it happened. We’re back. It’s justice!” “And to my mind, there’s no more reason to go through this madness. And, of course, we then did it for another decade.” “I think the military and the national security apparatus thought they could win. And I think that they also wanted to believe that because they had invested so much. People had died and they didn’t want them to die in vain.” “2011, Bin Laden is now dead. Why was it so hard to de-escalate?” Jeffrey Eggers was on President Obama’s National Security Council. He says that the goal since 9/11, to make sure Afghanistan would never again be a safe haven for terrorists, had become a recipe for endless war. “We will forever prevent the conditions that led to such an attack.” “Danger close!” [Gunfire] “And if you define it that way, when are you finished?” [Gunfire] “Go! Come on, come on, come on!” Though the surge failed to push back the Taliban, the U.S. drew down troop levels even as doubts were growing that Afghan forces would be able to defend the country. In 2021, President Biden, the fourth president to preside over the war, announced that he would withdraw U.S. troops, a plan set in motion by his predecessor, Donald Trump. “Nobody should have any doubts. We lost the war in Afghanistan.” “And we’re clear to cross?” “It wasn’t a peace agreement; it was a withdrawal agreement. The agreement was essentially, As we withdraw, don’t attack us.” As the U.S. leaves Afghanistan, the Taliban is taking over again, having quickly overrun the Afghan Army, which the U.S. spent more than $80 billion to train and equip. “The Taliban are out in full force. And their Islamist rule is already coming back.” “They can use this as a recruiting tool. They are now the champions of the jihadi movement because they pushed out the United States.” And U.S. officials are reflecting on the beginning of the war, 20 years after 9/11. “More people should have thought about endless war, not just in Congress but in the State Department, in the Defense Department, C.I.A. and elsewhere, in the White House. That the recipe of using military means to go after terrorism was just going to get us into one fight after another after another. One can only hope that Americans of the new generation will think about this.”