After 10 years of fighting in Afghanistan, US and Nato allies remain far from reaching their goals, a former commander of coalition forces has said.
Retired Army General Stanley McChrystal said the US began the war with a "frighteningly simplistic" view and still lacked the knowledge to achieve a successful end.
"Operation Enduring Freedom" aimed to track down Osama Bin Laden after 9/11 and eliminate the Taliban. The UN says more than 10,000 civilians have died in the past five years alone.
More than 2,500 international troops have been killed - most of them American.
The conflict has already surpassed Vietnam to become the longest war in US history.
'Superficial understanding'
Speaking at the Council on Foreign Relations, Gen McChrystal, who commanded coalition forces in 2009-10 before being forced to resign after a magazine interview, said the US and Nato allies were "a little better than" half way to achieving their military goals.
The most difficult task would be to create a legitimate government that ordinary Afghans could believe in and that would balance the influence of the Taliban, he said.
