Transcript of Bush on Whitehouse.gov (emphasis by me)
I went there [Bureau of Public Debt] because I'm trying to make a point about the Social Security trust. You see, a lot of people in America think there's a trust, in this sense -- that we take your money through payroll taxes and then we hold it for you, and then when you retire, we give it back to you. But that's not the way it works.
There is no "trust fund," just IOUs that I saw firsthand, that future generations will pay -- will pay for either in higher taxes, or reduced benefits, or cuts to other critical government programs.