Bush didn't want to know the location of the CIA's torture facilities

As long as the GOP held the Senate, the Bush administration could safely destroy the torture tapes, and, more importantly, they could safely lie about their non-existence.

So the decision to destroy them was a reasonable gamble. Rove really expected to hold the Senate. Heck, I though the GOP would hold the Senate. I'm surprised Lieberman still hasn't switched parties, for example.

They didn't, and so we have an investigation. It will, slowly turn up some interesting details. Like this one (emphasis mine):

Tapes by C.I.A. Lived and Died to Save Image - New York Times:

.... interviews with two dozen current and former officials, most of whom would speak about the classified program only on the condition of anonymity, revealed new details about why the tapes were made and then eliminated. Their accounts show how political and legal considerations competed with intelligence concerns in the handling of the tapes.

The discussion about the tapes took place in Congressional briefings and secret deliberations among top White House lawyers, including a meeting in May 2004 just days after photographs of abuse at Abu Ghraib prison in Iraq had reminded the administration of the power of such images. The debate stretched over the tenure of two C.I.A. chiefs and became entangled in a feud between the agency’s top lawyers and its inspector general. The tapes documented a program so closely guarded that President Bush himself had agreed with the advice of intelligence officials that he not be told the locations of the secret C.I.A. prisons.

Bush, of course, wanted plausible deniability, so he could say there were no prisons in Poland, etc. A lie of course, but an easier lie.

As usual the driving force behind the investigation is the cover-up. People tried to conceal the existence of the tapes, and then lied about their destruction. I think many people are wondering if Rove's retirement will turn out to be related to the cover-up process.

There will be other surprises that turn up as the cover-up is investigated...