Why did CIA Director Tenet resign 6 months before the election?

There are usually 3 reasons why government officials resign "for personal reasons" this close to a presidential election:

1. You are a drag on the ticket and you're asked to leave (so you can be morphed into the fall guy for one or more scandals).

2. You really do have personal reasons but it has to be like you are dying of cancer (or a member of your immediate family is dying of cancer).

3. You can no longer support the administration (which indicates that you are about to spill the beans and write a best seller... but it would be unethical to smear folks while they're still signing your paychecks).

Upon reflection...

It can't be Reason #1: George W. hasn't fired anyone so far. To do so would show weakness and a lack of his favorite self-descriptive "resolve" (which is, by the way, also the name of my favorite carpet stain remover).

As far as we know, there is no evidence to support reason 2: no one in Tenet's family is ill (and you can bet your bottom dollar that Matt Drudge would have posted this by now were it the case).

Why I choose reason #3:

George W.'s "Shaken, rattled, and rolled up into fetal position" demeanor as he announced Tenet's resignation.

The Bush administration has tried to blame the US Intelligence Community for its own PNAC/OSP blunders.

If Tenet writes a book and calls it What I learned From John Dean, we'll know it was most likely reason #3.