The real reason Afghanistan's military fell apart so quickly revealed by investigative reporter

CNN's Jake Tapper on Wednesday interviewed Washington Post reporter Craig Whitlock, who helped uncover an explosive set of documents in which American officials for years acknowledged they were losing in Afghanistan even while making rosy claims about the war in public.

While discussing the rapid collapse of the Afghan military in recent weeks, Whitlock said that Afghan troops' unwillingness to fight against the Taliban was only part of the problem.

"There was endemic corruption within the Afghan military leadership," Whitlock explained. "They were pocketing the salaries of their own troops, they were stealing fuel, they were stealing ammunition."

Given this, said Whitlock, it's not surprising that members of the Afghan military didn't want to fight.

"So if you're a front-line soldier with the Afghan army, where is your will to fight if your commander is leaving you out to dry?" he asked. "But the thing is, U.S. military officials have known this for more than a decade that there was not only a lack of will to fight, but that they were poorly equipped, poorly trained."

Compounding this failure, said Whitlock, was that the military brass put pressure on trainers to claim that the men they had trained were fully battle ready -- even if they were barely ready at all.

Watch the video below.

US put criminals in charge of Afghan military who 'stole their soldiers' salaries'