why wouldn’t they have?

In an excellent oral history of the Bush administration, a hole that reveals yet more holes:

November 1, 2001 A presidential executive order exempts presidents, vice presidents, and their designees from provisions of the 1978 Presidential Records Act and permits unclassified archived materials to be kept sealed in perpetuity, rather than being released after 12 years, as the law allows.

Robert Dallek, presidential biographer: I’ve testified twice before the House Oversight and Government Reform subcommittee, protesting this executive order. Now, there are two constraints that operate in relation to all executive materials. One is that if you’re going to violate someone’s privacy you are constrained from releasing the material. A much bigger issue is one of national security, and that’s what causes years to go by before many, many documents are released. So those are the two constraints.

But broadening this—and not only in relation to the president, but in relation to the vice president—reflects, I think, the Cheney proposition that the Watergate crisis put too many limitations on executive power.

And so we now have the issue of what sort of documentary record we’re going to find. I mean, this is a separate issue, I guess, but will they have sanitized the records?