The Bush administration took office at the end of an economic boom and left in the middle of a deep recession, with a budget surplus in 2001 becoming a $1 trillion-plus deficit by 2009. But Cheney said he and Bush had to spend money to deal with the September 11, 2001 attacks, the resulting war in Afghanistan, the disaster of 2005's Hurricane Katrina, and the costly and unpopular war in Iraq, now nearly six years old.

"All of these things required us to spend money that we had not originally planned to spend, or weren't originally part of the budget," Cheney said. "Stuff happens. And the administration has to be able to respond to that, and we did."