evidence: With the withdrawal of foreign forces from Afghanistan and the takeover by the Taliban, we've looked at how much the US and its Nato allies have spent in the country in 20 years of military operations. [...] He said: "After more than $2 trillion spent in Afghanistan... [or] you could take the number of $1tn, as many say." [...] As the US military shifted its focus away from offensive operations and concentrated more on training up Afghan forces, costs fell sharply to about $45bn in recent years.