The US combat mission in Afghanistan officially concluded last week, putting an end to the longest war in American history.
Roughly 13,000 troops, including 10,000 Americans, will remain in Afghanistan for two years to train and advise Afghan security forces.
On Sept. 11, 2001, al-Qaeda operatives hijacked four planes and crashed them into the World Trade Center, the Pentagon, and a field in Pennsylvania. Nearly 3000 people died.
Although none of the hijackers were Afghan nationals President George W. Bush declared a 'war on terror' that targeted al-Qaeda and Osama bin Laden, which received shelter and assistance from the Taliban regime in Afghanistan.
The US and Britain continued the bombing campaign in the run-up to an invasion of the country. Here, pro-Taliban Afghan refugees run toward members of the international press.
In early November 2001, a small number of Special Forces soldiers were deployed to Afghanistan to fight alongside the Northern Alliance, a loosely knit anti-Taliban coalition.
The Northern Alliance was formed mostly of guerrilla fighters and members of the military who had been ousted by when the Taliban took power in 1996. Despite receiving aid from both Russia and Iran, the alliance was not very well trained or cohesive.
Source: Global Policy Forum
Weakened by airstrikes, the Taliban eventually lost control of Kabul. Many of the city's residents, however, were left starving and homeless. The World Food Programme started its biggest ever food distribution in Kabul on Dec. 8, 2001.
By December Taliban forces had abandoned their last stronghold in Kandahar. The Tora Bora cave complex southeast of Kabul, where Bin Laden was believed to be hiding, was bombarded by US B-52s for two weeks. The Taliban had fallen but Bin Laden escaped along with Taliban leader Mullah Omar.
An interim government was formed by late December 2001. Hamid Karzai was sworn in as interim administration head on Dec. 22.
In March 2002 Afghan and American troops launched Operation Anaconda -- their first large-scale ground attack since their raid on the Tora Bora caves in December 2001. Troops moved to root out nearly 800 Taliban and al-Qaeda in the Shah-i-Kot Valley.
By May 2003, then-Defence Secretary Donald Rumsfeld announced that major combat operations had ended in Afghanistan. President George W. Bush declared 'mission accomplished' in Iraq that same day.
The war in Iraq diverted important resources away from Afghanistan, including US Special Operations forces. The Taliban took note, reasserting themselves in a concerted insurgent campaign that lasted for several years.
Despite the insurgency, Afghans voted in the country's first free legislative elections in more than 25 years on Sept. 18, 2005.
Despite the elections, the Taliban gained in strength and Karzai proved to be a duplicitous and unreliable ally. Afghanistan was backsliding. In February 2009, shortly after taking office, President Barack Obama said he would send an additional 17,000 American troops to the country in a surge that he hoped would 'stabilise a deteriorating situation in Afghanistan.'
On Oct. 3, 2009, 300 Taliban insurgents attacked the American Combat Outpost Keating in the mountains of eastern Afghanistan. Eight Americans and an estimated 150 insurgents were killed in one of the major battles of the war.
Six months later, in June 2010, Obama fired his top Afghanistan commander, Stanley A. McChrystal, after his aides were anonymously quoted attacking Obama in a Rolling Stone article. He was replaced by General David Petraeus, who would continue with counterinsurgency tactics that had proven successful during the Iraq surge.
But there was no quick fix to the war effort's problems. The results of Afghanistan's September 2010 parliamentary elections were disputed after reports emerged of ballot stuffing and voter suppression across the country. Recounts were ordered, and final election results were released on Oct. 31.
The most iconic US success of the war was just around the corner though. On May 2, 2011, US forces conducted a raid on a high-walled compound in Pakistan that killed al-Qaeda leader Osama bin Laden. President Obama hailed Bin Laden's death as 'the most significant achievement to date in our nation's effort to defeat al Qaeda.'
Source: New York Times
But the violence in Afghanistan continued. On Aug. 6, 2011, a US Army helicopter was shot down by insurgents in the eastern Afghan province of Wardak. Seven Afghan army soldiers and 22 Navy SEALs were killed.
In May 2012, Obama met with Hamid Karzai -- then in his 10th year of rule and widely considered to be a liability by decision-makers in Washington -- in Afghanistan and signed a Strategic Partnership Agreement. Obama then addressed the nation from Bagram Air Base, pledging to end the war by the end of 2014.
Making good on his 2012 re-election campaign promise, President Obama withdrew roughly 34,000 troops from Afghanistan between 2013 and the end of 2014, officially concluding America's combat mission on Dec. 28, 2014.
NATO's new Resolute Support mission will keep 13,000 troops -- mostly American -- stationed in Afghanistan for two years to train and advise Afghan security forces. Afghan soldiers are currently dying at a rate of about 100 per week at the hands of the Taliban. Much of the country is more stable than it was during the worst years of the war and Karzai peacefully handed over power after a disputed election. But the country's future is far from clear.
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