He emphasised that the Pakistanis played a double game in the fight against the Taliban; part ally and part hidden enemy.
He testified on Friday, July 19, at the first meeting of the commission investigating the US war in Afghanistan.
He stated that the US successfully defeated al-Qaeda and its safe havens in Pakistan with the help of the Pakistani military, but lost the war to the Taliban.
According to him, the main reason for this loss was the US' failure to eliminate Taliban safe havens in Pakistan.
Vickers explained that while the Pakistani military leadership supported the US in destroying al-Qaeda, they viewed the Taliban as a strategic tool to establish a government in Afghanistan that would serve Pakistan's interests.
Vickers also criticised the US counterterrorism strategy in Afghanistan, stating that it was flawed.
He said that the US failed to focus on its primary goal of combating terrorism while trying to build a nation in Afghanistan. He acknowledged that the US acted too late in creating a reliable and effective security force and subsequently wasted significant funds on building "wrong" security forces.
Vickers stated that the US transferred security responsibilities to the Afghan government too late.