On a few occasions before the September 11 attacks (including the day before), Secretary of Defense Donald Rumsfeld had made reference to over $2.3 trillion in transactions at the Pentagon which “cannot be tracked,” presumably meaning missing over the years due to fraud and waste.  In later statements he claims the issue has been partially resolved as the number is reduced to $700 billion.

Partial transcript from the above video: (View the full transcript at this link)

“On Sept. 10 [the day before the 9/11 attacks], Secretary of Defense Donald Rumsfeld declared war.  Not on foreign terrorists, ‘the adversary's closer to home.  It’s the Pentagon bureaucracy,’ he said.”

“‘According to some estimates we cannot track $2.3 trillion in transactions,’ Rumsfeld admitted.”

“$2.3 trillion— that's $8,000 for every man, woman and child in America.  To understand how the Pentagon can lose track of trillions, consider the case of one military accountant who tried to find out what happened to a mere $300 million.”

“Minnery, a former Marine turned whistle-blower, is risking his job by speaking out for the first time about the millions he noticed were missing from one defense agency's balance sheets.  Minnery tried to follow the money trail, even crisscrossing the country looking for records.”

“‘The director looked at me and said 'Why do you care about this stuff?’  It took me aback, you know?  My supervisor asking me why I care about doing a good job,’ said Minnery.”

“‘They have to cover it up,’ he said.  ‘That's where the corruption comes in.  They have to cover up the fact that they can't do the job.’”