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       Taliban fighters stand on a vehicle in Herat, Afghanistan's third biggest city on Aug. 13, the day after government forces pulled out.

       AFP via Getty Images

       Since the spring, Taliban assaults have brought more of Afghanistan’s cities and provinces under the extremist movement’s control. With U.S. troops preparing for a final withdrawal from the country after 20 years of war, the Afghan state is under serious threat and its people are at risk of a long humanitarian crisis that could encompass famine, war, displacement and human-rights abuses. Here’s a primer on the situation so far.

       Who are the Taliban? The Taliban (which means “students” in the Pashto language) are a Sunni political and military movement that, from 1996 to 2001, controlled most of Afghanistan, imposing on citizens a harsh interpretation of Islamic law. A U.S.-led invasion drove them from power soon after the 9/11 terrorist attacks in 2001 (whose mastermind, al-Qaeda leader Osama bin Laden, was a Taliban ally harboured in Afghanistan). For the next two decades, allied troops would try without success to eliminate the Taliban insurgency, while also preparing the fragile Afghan state to eventually take care of its own defence.

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       U.S. soldiers patrol the perimeter of a weapons cache near the U.S. military base in Bagram, Afghanistan, in 2003.

       Aaron Favila/The Associated Press

       Why is the U.S. withdrawing from Afghanistan? The “forever war” in Afghanistan has been costly for the U.S. and its allies, both in terms of lives lost and money spent. Three U.S. presidents have tried to set timetables for withdrawal: Barack Obama’s administration said in 2011 that withdrawal would begin in 2014, but after some major troops reductions, he halted the process; Donald Trump reached a peace deal with the Taliban and promised to get all troops out by May, 1, 2021, if they kept their commitments; and current President Joe Biden announced a plan this past April to withdraw by Sept. 11. In July, the U.S. military hurriedly gave the Afghans control of Bagram airfield, a strategically critical base north of the capital, Kabul.

       What do the Taliban want in Afghanistan now? The Taliban presence in southern Afghanistan never truly ended after the 2001 invasion, nor did they ever achieve their goal of recapturing the region – or even of expanding into the north of the country, which they didn’t control even at the height of their power. Since May, the Taliban have launched major offensives in both north and south, and by early August, provincial capitals began to fall, including Lashkar Gah in Helmand province and Kandahar, the Taliban’s former symbolic stronghold. On Sunday, the Taliban advance made its way into the capital Kabul, with the Afghan president fleeing the country. In areas under Taliban control, they’ve already begun to roll back the relative freedoms that women and religious minorities have had since the 2000s.

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       Canadian comrades of Trooper Michael Yuki Hayakaze, who was killed by a roadside bomb in southern Afghanistan, carry his coffin up the tarmac at Kandahar Air Field in 2008.

       Stephanie Levitz/The Canadian Press

       What is Canada’s role in Afghanistan? Canada ended its military mission in Afghanistan in 2011, by which point 158 Canadian Armed Forces members and seven Canadian civilians had died in the conflict. Ottawa continued to support Afghanistan with humanitarian and development aid and promised to continue doing so after the Americans left this summer. Later, as the situation deteriorated, Canada redeployed special forces to Afghanistan to help evacuate its Kabul embassy. Meanwhile, Prime Minister Justin Trudeau faced public pressure to bring Afghan interpreters and embassy staff (who would be vulnerable to Taliban reprisals) to Canada, and in July he announced a fast-tracked plan to do so for thousands of people.

       On Friday, Immigration Minister Marco Mendicino announced the government would also be helping resettle 20,000 Afghans who have already fled the country. On Sunday, The Canadian government temporarily closed its embassy in Kabul and has announced that its personnel were on the way back home, hours after the Taliban entered the capital and as former employees begged for help.

       How can I help ease the Afghan humanitarian crisis? Throughout the Afghan conflict, there have been various United Nations organizations and charities accepting donations to help Afghans through their dire straits. They include:

       Canadian Red Cross (Afghanistan campaign) UN High Commission for Refugees UN World Food Programme Islamic Relief Canada

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       With reports from Reuters and The Associated Press