The meaning of Cheney's note.

This note, written by Dick Cheney, has been entered into evidence in the Libby trial (h/t: Sullivan). It reads,

Not going to protect one staffer and sacrifice the guy (the Pres) that was asked to stick his neck in the meat grinder because of the incompetence of others.

If Plamegate is just a lot of "hyperventilating about nothing" created by the media as Putz has claimed again and again, what is this "incompetence" Cheney's referring to?