I respect you too much to want to engage in a major argument over this. As for evidence of Powell undermining the President in this and former administrations, though, please have a look at this, from the conservative think tank Center for Security Policy:
http://www.centerforsecuritypolicy.org/index.jsp?section=papers&code=02-D_44
Now, it's true that on the specific issue discussed in the article, inspections in Iraq, the Bush administration eventually changed its position. But the article details a number of ways in which Powell has been out of step.
I am not interested in a major argument. I just think that many of these "leaks" do not come from forces which are supportive of the President, and thus should be taken with a grain of salt. The link you provided gives some background on old policy decisions he supported, some of which were contrary to what we know NOW as the correct course.
If President Bush said "loathe" in a tape, I would be interested to know where Drudge got the tape.
Chris (section 9) brings out a point I had forgotten...that Alma Powell and Condi Rice are friends.
There is a great deal of mischief making in the Washington press. They do not get the 24/7 schmoozing that Clinton gave them, and they resentful. I would direct you to Bill Sammon's book on the war on terr, Fighting Back. There was no hint of this type of undermining in Sammon's book (although there was a lot of stuff which shows how odious Dana Milbank is...HA!).