Afghanistan War

The fall of Mazar-i-Sharif in November 2001 was the first major defeat for the Taliban following American intervention in Afghanistan. Taliban and al-Qaeda forces had held the city since 1998; their withdrawal ended that three-year control and opened the first significant urban center to Northern Alliance and U.S.-backed forces. Approximately 300 Taliban fighters were killed, 250 captured, and around 1,000 reportedly defected — losses that weakened Taliban cohesion at the outset of the campaign. The capture demonstrated that the combination of Northern Alliance ground forces and U.S. aerial bombardment could dislodge Taliban garrisons from fortified urban positions, establishing an operational template that would be applied across northern Afghanistan in the weeks that followed.

Taliban rule displaced

Operation Enduring Freedom was launched on 7 October 2001 as the direct U.S. military response to the September 11 attacks. President George W. Bush announced the commencement of airstrikes against al-Qaeda and Taliban targets in Afghanistan, opening what became the first stage of the Afghanistan War and the principal military expression of the broader global war on terrorism. The operation ran through 2014, encompassing a succession of U.S. commanders including Tommy Franks, David Petraeus, and others, while facing Taliban leadership under Mohammad Omar and al-Qaeda figures including Osama bin Laden and Ayman al-Zawahiri. Recorded casualties reached 66,000 on the coalition side and 72,000 for Taliban forces over the course of the conflict. Beyond Afghanistan, the OEF designation served as an umbrella for affiliated counterterrorism missions in other theaters, including OEF-Philippines and OEF-Trans Sahara, making it one of the most geographically expansive operational frameworks in modern U.S. military history.

Al-Qaeda leadership escaped contested pursuit

The U.S.-led invasion of Afghanistan, launched on 7 October 2001 in direct response to the September 11 attacks, marked the opening phase of what became a 20-year conflict. Its stated objectives were the dismantlement of al-Qaeda and the removal of the Taliban government that had provided al-Qaeda a base of operations. The United Kingdom joined as a primary coalition partner from the outset, alongside a broad multinational force. The invasion fundamentally reversed the military balance inside Afghanistan: the Northern Alliance, which had been losing ground to the Taliban since 1996 and had been confined largely to Badakhshan province and adjacent areas, was rapidly bolstered by American military support. At the time of the invasion, the Taliban controlled roughly 85 percent of Afghan territory, including Kabul. Coalition intervention effectively broke Taliban territorial dominance and ended the group's hold on the capital, setting the conditions for the post-Taliban political order. The operation also initiated the longer counterterrorism campaign that would define U.S. strategic priorities for the following two decades.

Operation Anaconda, fought in the Shah-i-Kot Valley and Arma Mountains southeast of Zormat, marked a significant threshold in the Afghanistan War as the first large-scale battle since the Battle of Tora Bora in December 2001. It was also the first operation in the Afghanistan theater to involve a large number of U.S. forces in direct combat roles, representing a shift from the earlier phase of the war in which CIA paramilitary officers and indigenous allies had carried the primary ground burden. The operation brought together U.S. military forces alongside CIA paramilitary personnel and their local allies in a coordinated effort to destroy al-Qaeda and Taliban fighters concentrated in the valley. Its scale and composition set a precedent for subsequent large-unit conventional combat operations in the post-2001 Afghan campaign.

Operation Red Wings was conducted in Kunar Province's Pech District during the summer of 2005 with the explicit aim of disrupting Taliban-aligned anti-coalition militia activity ahead of Afghanistan's September 2005 parliamentary elections. By targeting Ahmad Shah's militia group on the slopes of Sawtalo Sar, U.S. forces sought to reduce ACM influence in the region and create conditions stable enough to allow the National Assembly elections to proceed. Shah, a Nangarhar Province native with ambitions for broader standing among Muslim fundamentalists, represented the kind of localized but operationally significant threat that U.S. forces were working to suppress during this phase of the Afghanistan War. The operation illustrates the dual military-political logic that governed many U.S. actions in eastern Afghanistan during this period: combat operations were timed and shaped by the imperative to enable the Afghan state-building process, with electoral milestones serving as concrete near-term objectives.

The Battle of Chora was fought in Chora District, Uruzgan Province, in June 2007 between ISAF forces — primarily Dutch troops alongside Afghan allies — and Taliban-affiliated anti-coalition militias. The contest centered on the district's administrative center, which held strategic value as a key ground route connecting Gizab District in the north to the provincial capital of Tarinkot. Holding or losing Chora had direct implications for Taliban freedom of movement across Uruzgan Province. Press reports at the time characterized the engagement as the largest Taliban offensive of 2007 in Afghanistan, underscoring the scale of pressure ISAF and Afghan forces faced in the province that year. The battle resulted in the death of one Dutch soldier, along with approximately 50 to 80 civilians and 70 Taliban fighters — a casualty profile that reflected both the intensity of the fighting and the costs borne by the local population during contested district-level engagements.

The Battle of Musa Qala was a British-led ISAF operation in Helmand Province that resulted in the recapture of Musa Qala from Taliban control. Over three days of intense fighting, a force of approximately 4,500 ISAF and Afghan National Army troops engaged an estimated 2,000 Taliban fighters. The Taliban withdrew into the surrounding mountains on 10 December, and Afghan Army troops formally pushed into the town centre on 12 December. The operation was notable for the prominent role of Afghan National Army forces in the assault, with Afghan troops leading the entry into the town — a symbolic and operational marker of the Afghan state's growing military participation in reclaiming contested districts in Helmand Province.

Operation Achilles, launched on 6 March 2007, was the largest NATO-led offensive mounted in Afghanistan up to that point, committing some 4,200 NATO troops against an estimated 10,000 Taliban fighters in Helmand province. Its stated objective was to clear the province of Taliban presence. NATO reported approximately 1,000 Taliban casualties. A notable finding from the operation was that Taliban commanders, including Dadullah and Abdul Qassim, directed their forces away from direct confrontation, instead adopting guerrilla tactics — a shift that complicated the conventional clearing mission and signaled an adaptive insurgent response to large-scale NATO pressure in Helmand.

The assault on Combat Outpost Keating by approximately 300 Taliban fighters in Nuristan Province on October 3, 2009, became the bloodiest engagement for U.S. forces in Afghanistan since the Battle of Wanat in July 2008, which had occurred roughly 20 miles away. Eight Americans were killed and 27 wounded, while Taliban losses reached an estimated 150–200 killed or wounded. The battle intensified scrutiny of the U.S. strategy of establishing isolated outposts in remote, difficult terrain in eastern Afghanistan, where small garrisons faced the risk of being overwhelmed by massed insurgent attacks far from reinforcement. Coming at a moment of broader debate over force posture and troop levels in the war, Kamdesh underscored the operational vulnerabilities created by forward positions that were tactically difficult to defend and logistically exposed.

Operation Strike of the Sword (also known as Operation Khanjar) was the largest Marine offensive since the Battle of Fallujah in 2004 and represented a major commitment of U.S. ground forces to Helmand province in southern Afghanistan. Deploying approximately 4,000 Marines from the 2nd Marine Expeditionary Brigade alongside 650 Afghan troops and NATO air support, the operation marked a significant escalation of coalition efforts in one of Afghanistan's most contested regions. The offensive also constituted the biggest airlift operation by the Marines since the Vietnam War, underscoring the logistical scale of the push into the Helmand River valley. The operation reflected the broader U.S. strategy of extending Afghan government authority into Taliban-held territory in the south during the early surge period of the war.

Operation Moshtarak, conducted in Marjah, Helmand Province, was the largest joint operation of the Afghanistan War up to that point, combining Afghan, American, British, Canadian, Danish, and Estonian forces in a single coordinated offensive. Its stated objective was to remove the Taliban from Marjah and eliminate what was described as the last Taliban stronghold in central Helmand Province. The town had been under Taliban and drug-trafficker control for years, making it a significant logistical and political target. The scale of the operation — 15,000 troops across multiple coalition nations — reflected the McChrystal-era emphasis on population-centric counterinsurgency and the strategic importance placed on securing Helmand as a whole. Taliban casualties were recorded at 120, though the operation's longer-term effect on Taliban presence in the province remained a subject of assessment beyond the initial offensive.

The Resolute Support Mission marked the formal transition of NATO's role in Afghanistan from a combat operation to an advisory and training mission. It succeeded the International Security Assistance Force on 28 December 2014, with RSM beginning on 1 January 2015 under United Nations Security Council Resolution 2189. Rather than conducting direct combat operations, the mission focused on advising and training Afghan security forces to sustain long-term security independently. Framed under the U.S.–Afghanistan Strategic Partnership Agreement, RSM was originally structured to run through at least 2024, signaling a shift from coalition-led fighting to Afghan institutional capacity-building as the primary Western strategic objective in the country.

The U.S.–Taliban agreement signed in Doha in February 2020 set the terms for ending the longest major American war. Under the deal, NATO committed to withdrawing all forces by a specified deadline in exchange for Taliban counter-terrorism commitments. A direct consequence of the agreement was a sharp reduction in U.S. air strikes against the Taliban, a shift that materially degraded the Afghan National Security Forces' capacity to contest the Taliban insurgency. The withdrawal, completed on 30 August 2021, formally closed the 2001–2021 U.S. war in Afghanistan after cumulative NATO casualties of over two thousand. The Doha framework effectively transferred the burden of territorial defense entirely to Afghan government forces at the moment their most significant source of air support was curtailed.

The 2021 Taliban offensive ended the nearly 20-year war in Afghanistan by bringing down the Islamic Republic of Afghanistan and restoring Taliban control of the country. Despite a substantial numerical disadvantage in recorded force sizes, the Taliban achieved a decisive strategic outcome, in part through a continuation of negotiated and paid surrenders that had begun following the February 2020 US–Taliban deal. This bottom-up process of capitulation, proceeding from the village level upward, eroded the republic's territorial coherence before conventional resistance could consolidate. The Taliban victory carried widespread domestic and international consequences, including concerns over human rights and the potential proliferation of terrorism, marking a definitive conclusion to the U.S.-led intervention that had begun in 2001.

Taliban victory

A counterterrorism campaign became a long war of governance and insurgency.

The U.S. war ended with a strategic reversal of its central political objective.