Nearly twenty years after the U.S. military began operations against the Taliban in Afghanistan, President Joseph R. Biden reported on August 31, 2021, that the last U.S. combat troops had departed the country. Biden announced on April 14, 2021, that the United States would withdraw combat troops from Afghanistan before the twenty-year anniversary of September 11, 2001, and NATO member states decided to depart the country simultaneously. The withdrawal followed an early 2020 deal between the Taliban and the Trump administration, which conditioned the pullout on Taliban agreement not to harbor terrorists that target the United States and its allies. Over the course of a week and a half in mid-August, the Taliban captured most of Afghanistan's provincial capitals, entering Kabul on August 15. The Afghan government collapsed, and President Ashraf Ghani fled the country. Through the end of August, the United States and other countries conducted a major airlift operation to evacuate their nationals and Afghans considered at risk of Taliban reprisals, though many were left behind amid risks of renewed civil war and humanitarian crisis.
In an Authorization for Use of Military Force (AUMF) passed on September 18, 2001, Congress authorized the president to “use all necessary and appropriate force” against those involved in or harboring those involved in the September 11 attacks,Footnote 1 and the United States began military operations against the Afghan Taliban on October 7, 2001.Footnote 2 U.S. forces in Afghanistan peaked in 2011 at more than 100,000 troops,Footnote 3 dropping to about 3,500 by March 2021.Footnote 4 Over the course of two decades, the conflict in Afghanistan resulted in the deaths of 2,461 U.S. service members and personnel, as well as 20,722 wounded,Footnote 5 and the deaths of nearly 4,000 U.S. contractors.Footnote 6 The toll on Afghan forces and civilians was far higher. Between 2001 and early 2021, 66,000 Afghan soldiers died,Footnote 7 and more than 46,300 civilians were killed.Footnote 8 The conflict cost the United States more than two trillion dollars.Footnote 9
In February 2020, the Trump administration reached an agreement with the Taliban that provided for a fourteen-month drawdown of U.S. forces in exchange for Taliban assurances that the group would prevent actors within its territory from attacking the United States and its allies.Footnote 10 Although Trump initially proposed withdrawal of troops by the 2020 election,Footnote 11 the administration eventually settled on a deadline of May 1, 2021.Footnote 12
In mid-April 2021, President Biden announced that while the United States would “begin [its] final withdrawal” on May 1, “U.S. troops, as well as forces deployed by our NATO Allies and operational partners, will be out of Afghanistan before we mark the 20th anniversary” of the September 11 attacks.Footnote 13 Biden declared that “[I]t's time to end the forever war.”Footnote 14 He explained that the United States “went to Afghanistan in 2001 to root out Al Qaeda, to prevent future terrorist attacks against the United States planned from Afghanistan,” and that the country “accomplished that objective” in the ensuing years.Footnote 15 Pointing to terrorist threats “metastasizing around the globe,” Biden declared:
We cannot continue the cycle of extending or expanding our military presence in Afghanistan, hoping to create ideal conditions for the withdrawal, and expecting a different result. I'm now the fourth United States President to preside over American troop presence in Afghanistan: two Republicans, two Democrats. I will not pass this responsibility on to a fifth.Footnote 16
Biden explained that although the United States “will not stay involved in Afghanistan militarily,” it would continue its “diplomatic and humanitarian work,” as well as “providing assistance to the Afghan National Defense and Security Forces.”Footnote 17
NATO member states agreed unanimously to pull troops out of Afghanistan, and NATO announced the alliance's departure alongside the U.S. decision.Footnote 18 NATO Secretary-General Jens Stoltenberg stated, “[w]e went into Afghanistan together. We have adjusted our posture together. And we are united in leaving together.”Footnote 19 He added that “NATO Allies and partners will continue to stand with the Afghan people. But it is now for the Afghan people to build a sustainable peace.”Footnote 20
Congressional reaction to the withdrawal fell largely along party lines. House Speaker Nancy Pelosi (D-CA) described the process as a “safe, strategic and orderly departure” and noted that she “support[s] this transition” while emphasizing, “[i]t is imperative that the hard-won gains secured by and for Afghan women and girls are not erased.”Footnote 21 Senate Armed Services Committee Chairman Jack Reed (D-RI) stated that, “[t]here are no good options in Afghanistan,” and that “Biden is making a tough call on what may be the least of many bad options.”Footnote 22 Senate Republican Leader Mitch McConnell (R-KY) criticized the withdrawal, saying that it “leaves our Afghan partners alone to confront threats that [Biden's] own top advisors acknowledge are grave and growing worse.”Footnote 23 McConnell added that he hoped the administration would “delay the withdrawal, address these concerns, and reconsider its misguided retreat.”Footnote 24 Senate and House Armed Services Committee ranking members Jim Inhofe (R-OK) and Mike Rogers (R-AL) condemned the plan as a “political, calendar-based approach,” calling it “irresponsible to leave when conditions on the ground would lead to a civil war in Afghanistan and allow the country to become a safe haven for terrorists once again.”Footnote 25
Afghan President Ashraf Ghani stated that Afghanistan “respects the U.S. decision and we will work with our U.S. partners to ensure a smooth transition.”Footnote 26 For its part, the Taliban objected to the extension of the withdrawal timeline, stating that a delay beyond May 1 was “not acceptable,”Footnote 27 and promising “problems” in the event the “agreement is breached.”Footnote 28 However, the group stopped short of abrogating the agreement or engaging in widespread attacks on departing forces.
China and Russia expressed concerns about the consequences of U.S. withdrawal. Russia called the U.S. extension a “clear violation” of the agreement to pull out by May 1, but also found “concerning” the potential that “the armed conflict in Afghanistan might escalate in the near future, which in turn might undermine efforts to start direct intra-Afghan negotiations.”Footnote 29 Chinese officials stated that “[t]he United States, which created the Afghan issue in the first place, should act responsibly to ensure a smooth transition.”Footnote 30 Officials worried that the speed of the withdrawal would lead to instability, as well as increased space for terrorists.Footnote 31
Despite U.S. promises of continued support, as well as resumed airstrikes against the Taliban,Footnote 32 the militants quickly routed the Afghan military in mid-August. In April, Afghan President Ghani stated on Twitter that “Afghanistan's proud security and defense forces are fully capable of defending its people and country, which they have been doing all along.”Footnote 33 However, the Afghan government remained fractured,Footnote 34 and the military continued to rely on foreign contractors to maintain its equipment.Footnote 35 Between mid-April and late July 2021, the Taliban increased its territory to control 223 of the country's 419 districts.Footnote 36 On August 6, 2021, the Taliban took control of a provincial capital in southwestern Afghanistan.Footnote 37 By August 13, Taliban fighters seized the cities of Herat, Kandahar, and Lashkar Gah with little resistance.Footnote 38 On August 15, the Taliban entered Kabul and Bagram airbase, and President Ghani fled the country.Footnote 39
The speed of the collapse appeared to take U.S. officials by surprise. A late June intelligence report had estimated that the government could fall within six months to a year of the U.S. departure.Footnote 40 On August 18, the chairman of the Joint Chiefs of Staff asserted, “[t]here was nothing that I or any other of us saw that indicated a collapse of this army and this government in 11 days.”Footnote 41 However, despite the Afghan government's collapse, President Biden stated:
I stand squarely behind my decision. After 20 years, I've learned the hard way that there was never a good time to withdraw U.S. forces. . . . Afghanistan political leaders gave up and fled the country. The Afghan military collapsed, sometimes without trying to fight. If anything, the developments of the past week reinforced that ending U.S. military involvement in Afghanistan now was the right decision.Footnote 42
The fall of the Afghan government prompted a multilateral effort to evacuate foreign nationals, as well as Afghans at risk of Taliban reprisals. The evacuations followed concerns by U.S. and other officials that the Taliban would target people who worked with the Afghan government and allied forces. Media outlets reported in mid-July that Taliban fighters had executed twenty-two Afghan soldiers who attempted to surrender,Footnote 43 and in early August, the U.S. and UK embassies in Kabul expressed concern over the Taliban's murder of civilians, asserting that the killings “could constitute war crimes.”Footnote 44 In late July, the United States began transporting to U.S. military bases the first of approximately 18,000 Afghans who applied for special immigrant visas to travel to the United States.Footnote 45 The United States also expanded refugee programs to cover Afghans who worked for U.S.-funded programs, as well as U.S. media and nongovernmental organizations.Footnote 46 The United Kingdom accelerated plans to resettle Afghans who worked for the British military and the UK government, as well.Footnote 47 The Biden administration received criticism for failing to evacuate more vulnerable Afghans prior to the Taliban's advance,Footnote 48 but responses to resettlement of Afghan refugees in the United States and elsewhere have been mixed, with European countries hesitant to accept large numbers of AfghansFootnote 49 and Russia objecting to their relocation within Central Asia.Footnote 50
The United States maintained control of Kabul's Hamid Karzai International Airport to facilitate the departure of U.S. personnel and others in the wake of the Taliban takeover, temporarily deploying 6,000 troops to secure the airport.Footnote 51 In one of the largest airlifts in history, the United States evacuated more than 123,000 people, including 6,000 U.S. nationals, between August 14 and 30.Footnote 52 An August 26 suicide bombing by Islamic State-Khorasan (ISIS-K) in a crowd outside an airport gate resulted in the deaths of 170 Afghan civilians and thirteen U.S. servicemembers, marking the last U.S. casualties of the war in Afghanistan.Footnote 53 The final U.S. forces departed the airport on August 30.Footnote 54
The United States was unable to evacuate a significant number of Afghans who assisted in the war.Footnote 55 However, approximately one hundred countries issued a joint statement emphasizing “the clear expectation of and commitment from the Taliban” that individuals inside the country would be allowed to travel abroad freely.Footnote 56 The Taliban confirmed that Afghans “may leave the country anytime they want to.”Footnote 57 In a resolution on August 30, the UN Security Council noted that it “expects that the Taliban will adhere to these and all other commitments.”Footnote 58
On August 31, President Biden announced that “[l]ast night in Kabul, the United States ended 20 years of war in Afghanistan—the longest war in American history.”Footnote 59 Defending his decision not to push back the deadline for withdrawal, Biden stated “I was not going to extend this forever war, and I was not extending a forever exit.”Footnote 60 Noting that the “decision about Afghanistan is not just about Afghanistan,” Biden suggested more generally that he was bringing to an end “an era of major military operations to remake other countries,” and he emphasized the need to focus on the “vital national interests of our people.”Footnote 61 While noting that “human rights will be the center of our foreign policy,” he made clear that “the way to do that is not through endless military deployments, but through diplomacy, economic tools, and rallying the rest of the world for support.”Footnote 62 The Taliban celebrated the departure of U.S. troops, announcing that “[t]he last American soldiers departed from Kabul airport, and our country has achieved a full independence, thanks to God.”Footnote 63
It remains unclear precisely how the international community will interact with the Taliban going forward.Footnote 64 U.S. Secretary of State Antony Blinken stated that “[a] new chapter of America's engagement with Afghanistan has begun. . . . The military mission is over. A new diplomatic mission has begun.”Footnote 65 He continued, “[t]he Taliban seeks international legitimacy and support. Our message is: any legitimacy and any support will have to be earned.”Footnote 66 However, U.S. capacity to engage with and monitor the Taliban government remained limited after the United States closed its embassy in Kabul, moving its Afghanistan office to Qatar.Footnote 67 For its part, Russia announced plans to “normalize” relations with Afghanistan and called for the unfreezing of assets, as well as international assistance to bolster the country's economy under Taliban rule.Footnote 68 China hoped the international community would engage with and “positively guide” the Taliban.Footnote 69
Humanitarian conditions in Afghanistan continue to deteriorate, and the Taliban's return poses additional risks. Relief actors estimated that 18.4 million people—nearly half the Afghan population—would require humanitarian assistance during 2021, nearly six times the number in need compared to 2018.Footnote 70 The United Nations expects acute food insecurity to represent the most pressing concern,Footnote 71 with drought, conflict, and disrupted trade flows expected to exacerbate the problem.Footnote 72 Between January and early August 2021, conflict also displaced more than 550,000 people throughout the country.Footnote 73 A UN official declared that “[t]he situation has all the hallmarks of a humanitarian catastrophe.”Footnote 74 Many anticipate that Taliban rule will reverse the gains made by Afghan women since 2001, given that the Taliban barred women and girls from schools and most jobs from 1996 to 2001.Footnote 75 There is also a risk of civil war.Footnote 76
Although it is unclear whether or to what extent the Taliban will again provide refuge to Al Qaeda and similar organizations,Footnote 77 Biden has emphasized that counterterror operations in Afghanistan will continue.Footnote 78 U.S. officials expect the withdrawal of combat troops to complicate such efforts, but the commander of U.S. Central Command has said that “[i]t's going to be extremely difficult to do it, but it will not be impossible” to conduct “over the horizon” counterterror operations in Afghanistan.Footnote 79 In a possible preview of such operations, on August 27, the United States used a drone launched from a base in the United Arab Emirates to strike an ISIS-K “planner” and “facilitator” in Jalalabad in response to the suicide bombing at the Kabul airport.Footnote 80 The risk of such operations was made vivid, however, by another strike on August 29. The U.S. military struck a car in Kabul in an effort to thwart what they believed to be another ISIS-linked suicide bomber, but weeks later admitted that the strike was a “tragic mistake,” killing a man who worked for a U.S. aid organization and nine members of his family, including seven children.Footnote 81
The withdrawal of combat troops also poses forward-looking legal and policy questions for the United States. Congress is considering repealing and replacing the 2001 AUMF,Footnote 82 and lawyers for individuals captured in Afghanistan and held at Guantánamo Bay have argued that the end of direct U.S. involvement in the conflict means the United States lacks a legal basis to continue to hold the detainees.Footnote 83 The Justice Department has responded that the United States “remain[s] at war with Al Qaeda,” and that the “war on terrorism” is not over.Footnote 84