In 2001 an international coalition led by the USA invaded Afghanistan to destroy terrorist organisation Al-Qaeda when the Taliban refused to hand over Osama bin Laden. British forces went in alongside US troops. At the height of the conflict there were more than 130,000 NATO troops on the ground. By July 2021, nearly all NATO countries had fully withdrawn.

But, after 20 years of conflict, the Taliban again claim to be in control of Afghanistan.

In this video, we look at how the war in Afghanistan began, what Britain’s role was, and why the war lasted for 20 years.

Afghanistan War

In 2001 an International Coalition led by the USA invaded Afghanistan. The Taliban regime were removed from power and a new government was formed.

At the height of the conflict that followed, there were more than 130,000 NATO troops on the ground. 3,500 coalition troops were killed in action, 70,000 from the Afghan Security Forces and tens of thousands of civilians.

Now, after twenty years of conflict, the Taliban, again claim to be in control of Afghanistan. So how did the war begin, what was Britain’s role and why did it last for 20 years?

Biden: "Our objective was clear; the cause was just; our NATO Allies and partners rallied beside us."

Trump: "The Taliban wants to make a deal; we'll see if they want to make a deal; it's got to be a real deal..."

Obama: "And so we went to war against Al-Qaeda to protect our citizens, our friends and our allies."

Bush: "The search is underway for those who are behind these evil acts; a great people has been moved to defend a great nation."

The events of September 11 2001 shook the world. People watched across the globe as news reels showed a Boeing 767 crash into the North Tower of the World Trade Centre just before 9am, in what initially appeared to be a terrible accident. When a second plane crashed into the South Tower 18 minutes later, it became clear that this was an attack. A third plane crashed into the Pentagon, just outside Washington, DC, and the fourth plane crashed in rural Pennsylvania after the crew and passengers brought down the terrorists on board. 3,000 people were immediately killed in these attacks.

The hijackers were terrorists from Saudi Arabia and other Arab nations. Al-Qaeda – a terrorist network led by Osama bin Laden - was quickly identified as being responsible for the 9/11 attacks.

Within 10 days, US President George W Bush declared a 'War on Terror' and stated that defeating terrorism was now the world’s fight.

So what link did Al-Qaeda have with Afghanistan?

Amanda Mason: "So the leaders of Al-Qaeda have been based in Afghanistan since the 1990s running training camps there. The American Government issued an ultimatum to the Taliban Government that ran Afghanistan at this time, demanding that they hand over all Al-Qaeda personnel still in the country and close the training camps. When the Taliban refused, military action seemed increasingly likely."

A month after 9/11, the invasion began, as America launched air strikes against Afghanistan.

Amanda Mason: "American special forces liaised with and fought alongside anti-Taliban groups known as the Northern Alliance, forcing the Taliban from their strongholds in Masari Sharif, Kandahar and Kabul. Despite a fierce battle in the Tora Bora mountains, bin Laden escaped capture and fled across the border into Pakistan."

With most of Al-Qaeda driven out of Afghanistan, bin Laden gone, and the Taliban regime at an end, it might seem that the US had achieved most of their goals. So why did troops stay behind?

Amanda Mason: "At the end of 2001, a new transitional government was formed and to help support it. The International Security Assistance Force, ISAF, was set up and was initially led by the UK. As part of a wider effort to help rebuild the country, the UK ran a provincial reconstruction team or PLT. America, Germany and New Zealand also operated teams across the country. American troops were still carrying out some anti-terrorist operations against remaining Al-Qaeda resistance but they were anxious to avoid being seen as an occupying force or to get too involved in the reconstruction."

In 2002, America’s focus switched to Iraq.

Bush: 'Saddam Hussein and his sons must leave Iraq within 48 hours'. 

In 2003, President Bush declared that major combat operations in Afghanistan were at an end and it was now a period of ‘stability, stabilisation and reconstruction activities’.

Hopes remained high that this was a positive new beginning for Afghanistan. Efforts at reconstruction continued in Afghanistan, with the UK, Germany, the US, Japan and Italy each taking responsibility for key areas such as policing, disarmament, the Afghan Army, the judiciary and counter-narcotics. But progress was slow. Many of the ‘warlords’, who had wielded power before the Taliban took control in the 1990s, were given positions in the government by the new President. Continuing American counter-terrorism operations were unpopular and often resulted in civilian casualties. It was in this environment that Taliban fighters returning to Afghanistan began to gain support.

With the Taliban in the ascendancy again, it was increasingly uncertain how long ISAF would be able to keep the peace...

In 2004, as part of the NATO expansion, Britain agreed to take responsibility for Helmand in the south. But over time this mission changed from a peacekeeping mission to fighting a war.

Amanda Mason: "So Britain seems to have taken responsibility for Helmand province largely because the Canadians had already volunteered to take over neighbouring Kandahar. In-depth knowledge of Helmand and its complex politics was limited. A member of the special forces was reputed to have warned: 'There's no insurgency in Helmand now but if you want one you can have one.'

The initial plan for the British in Helmand recommended that their troops should be based around the central towns of Lashkar Gah and Gereshk, where they could create a secure environment for development projects. But as soon as British troops started arriving in Helmand in spring 2006 their commanders faced pressure to provide a military presence across the whole of the province."

Troops were dispatched to the north of Helmand, which provoked a furious response from the resurgent Taliban who'd been returning to Helmand in large numbers for the past year.

Amanda Mason: "By the end of summer 2006, British troops were under fire and effectively under siege in a series of fortified buildings known as platoon houses. The next brigade into Helmand tried to wage a mobile war against the Taliban but soon became overstretched."

Greater troop numbers meant that the Third Brigade could continue to take an aggressive approach but any gains were short-lived. From 2008, British strategy in Helmand shifted. An influx of US troops in the south meant that UK forces could concentrate larger numbers in the centre of the province. As ‘clearance’ operations were completed, more troops could hold the area to deter insurgents from returning, enabling development to take place.

Commanding Officer: "There's an a A company and B company, two RGR who are actually clearing enemy positions to allow the space for civilian reconstruction and development. We're clearing that then to allow the IEDD Team to clear IEDs from an area."

Once the British had left Iraq in 2009, Britain’s entire military effort focused on Afghanistan. But the fight was getting increasingly difficult, and casualty figures had started to rise…

Amanda Mason: "Because British forces in Helmand operated from a series of static control bases, the Taliban were able to encircle these with IEDs, slowing and restricting the movement of troops beyond the bases and contributing to a steep right in British casualties."

2009 proved to be the costliest year for British forces, with 108 killed and 157 seriously injured. Support for British troops remained high and new service charities were formed. There was intensive media coverage of repatriations.

Amanda Mason: "But public confidence in and support for the war in Afghanistan was waning, further undermined by revelations about the Iraq War."

In 2010, UK troop numbers reached their peak, with around 10,000 troops deployed across Afghanistan. This was part of the US surge strategy announced by Barack Obama in 2009.

Two years later in 2011, Osama Bin Laden was killed in Pakistan by US Special Forces.

Obama: "I can report to the American people and to the world that the United States has conducted an operation that killed Osama bin Laden, the leader of Al-Qaeda."

Osama bin Laden was the main reason that US troops had originally been in Afghanistan. Now Obama announced that troop withdrawal would begin. Similar announcements from other nations soon followed. UK Prime Minister, David Cameron, said that all British combat missions would be finished by the end of 2014.

Once the withdrawal timeline had been announced, efforts to train Afghanistan’s own security forces were stepped up. But were they ready to take over?

Amanda Mason: "So by 2010, there were more than 130,000 soldiers in the Afghan Army and some units had started leading their own operations."

There were also several high-profile green on blue attacks where Afghan forces attacked the international troops mentoring or training them, highlighting that many issues remained. The Taliban also remained active throughout this, and in 2012 launched a large-scale operation against ISAF and the Afghan forces. The British base at Camp Bastion was also attacked.

Amanda Mason: "As Afghan forces began to take over more of the fighting, their casualty rates also increased. Civilian casualties remained high and they were often victims of indiscriminate IED attacks."

American and NATO troops officially ended their combat mission in 2014. Camp Bastion was handed over to Afghan forces and the last British troops left in October. In 2015, NATO announced the start of its ‘Resolute Support Mission’ to offer continued military training and support, particularly in artillery, logistics, medical, counter-IED and intelligence. Britain was part of this NATO mission, sending around 1,000 troops to Afghanistan every year.

Amanda Mason: "Despite continued international support, the Afghan forces were unable to prevent further Taliban gains. A major Taliban offensive in Helmand almost led to the loss of the provincial capital Lashkar Gah in 2018. US airstrikes were increased but even this new initiative couldn't reverse Taliban advances.

The military situation seemed to be at a stalemate.

Through 2018 and 2019, efforts were being stepped up to find a negotiated end to the conflict. In 2020, America and the Taliban signed a peace agreement in Qatar. The provisions included the withdrawal of American and NATO troops from Afghanistan, a Taliban pledge to prevent Al-Qaeda from operating in areas under Taliban control, and talks between the Taliban and  Afghan Government, which finally began in September.

In April 2021 new US President Joe Biden announced that the remaining 2,500 US troops would be withdrawn from Afghanistan by 11 September 2021.

Biden: "I've concluded that it's time to end America's longest war; it's time for American troops to come home."

By the middle of summer, almost all international forces had been withdrawn.

Amanda Mason: "Since then, the Taliban have taken advantage of the withdrawal of international forces, capturing territory in rural areas before moving on to take control of major cities, something they had not previously managed to do since they were ousted in 2001."

At the time of making this video, the world is waiting to see what the future holds for Afghanistan.

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