The last few days have seen the culmination of the Taliban’s lightening offensive across Afghanistan, retaking all the lands lost to the American forces over the course of the 20-year US effort.

In the two decades since 11 September 2001 the United States had attempted to bring about a stable democratic government that could resist any future attacks from the Taliban but that notion has crumbled with embarrassing speed.

The full extent of the failure will become apparent in the months and weeks to come but it is already clear that the US government has spent an astonishing amount of money in search of an outcome that has proved entirely unrealistic.

Across the last 20 years, Brown University’s Costs of War Project has estimated that the US has spent $2.26 trillion on the conflict in Afghanistan.

How did the US spend trillions in Afghanistan?

The study from Brown University brings together various avenues of spending that relate to the war in Afghanistan, including costs associated with operations in Pakistan, which was used as a base for much of the time. These figures do not include the cost of lifetime care that the US government is obliged to spend on American war veterans involved in the conflict.

Most chillingly, they estimate that 241,000 people have lost their lives as a direct result of the War in Afghanistan. This does not include indirect consequences of war, such as those who died due to loss of access to food, water or infrastructure.

Efforts to retrain military and police forces fell short

One of the key aims throughout the American involvement in Afghanistan was to train the Afghan forces to ensure that they would one day be able to resist the Taliban without US assistance. In 2019 the New York Times estimated that around $87 billion had been spent on that effort, but even then there was scepticism about the effectiveness of the training.

They reported then that the Afghan army “suffers from increasing casualty rates and desertion”, meaning that up to a third of the force has to be retrained each year. Efforts to return military authority to the Afghans in 2014 proved unsuccessful and President Barrack Obama soon reversed the decision when it became clear that the Taliban had regained ground.

Speaking to NPR on Sunday, military analyst Jason Dempsey explained that the US had never overcome the “fundamental challenge” of the effort to strengthen the Afghan military.

He said the US had “built an Afghan National Army for a nation that simply doesn't exist,” which “kind of contributed to the speed with which everything collapsed this week.”