Best when changed frequently.

This seems to be the message suggested by a summary tacked to the end of an Associated Press article about when exactly Rumsfeld will sign out and Gates will punch in:

There has been speculation that the Pentagon transition would be put off until the end of December in order to give Rumsfeld the distinction of being the longest-serving secretary of defense since the post was created in 1947.

Rumsfeld is the only person to have held the job twice. The first time, he served for 14 months, from Nov. 20, 1975 to Jan. 20, 1977. His current tenure began Jan. 20, 2001. If he were to stay until Dec. 28, his combined tenures would surpass the longevity record held by Robert S. McNamara, who served from Jan. 21, 1961 to Feb. 29, 1968.

Ruff said, however, that the timing of Gates' takeover has nothing to do with the longevity record.

"I can assure you that is not a factor on the secretary's mind," Ruff said.

McNamara, of course, has grown old enough to regret much of what he did during his tenure in that post. Will Rummy be around long enough to realize how much he screwed up and how much death and destruction his incompetence rained down upon the American and the Iraqi peoples? Does he have it in him to find his own shortcomings and share what those who attain the heights of power as he has should learn from them?

I sure do doubt that one, especially if Bush goes ahead and pins another Medal of Freedom on another dubious chest.

It's interesting how Rumsfeld and McNamara are almost like mirror images. Charlie Savage's Boston Globe article on Sunday about Cheney's lust for untrammeled executive power was a good reminder of how Rumsfeld started his career in presidential politics - running the Office of Economic Opportunity, whose antipoverty mission he apparently held in rather low regard. After gutting OEO, he moved on up to Secretary of Defense in the Ford administration. And, of course, our brilliant Decider gave him a second chance in 2001 where he showed that you really can't teach very old dogs how to carry out basic motor functions, let alone new tricks.

McNamara, of course, went from the international war on peace to the global war on poverty (which, let's face it, he probably won't be remembered for very positively). He left powerful marks on both institutions, and at the end of his life, seems regretful of much of what he was responsible for. While Rumsfeld's legacy is beamed over by people who want to name the entire country after Ronald Reagan, it's useful to keep McNamara's sense of his own legacy in mind.

Running our nation's armed forces is hard work. It seems like letting the same people do it for eight years at a time twice now hasn't been all that good for our country. Rowan Scarborough's article in the Washington Times today shows how Robert Gates has a long-standing reputation for being on the wrong side of many fights in our nation's national security administrivia, and so it would seem that the Decider has selected another turkey again. There isn't much we're going to be able to do to make our Department of Defense better functioning in the last two years of the Bush Administration/Cheney War Cabinet.

But there's a message that whoever comes after him should certainly take away, whether it's Hillary, Obama, Rudy, or McCain: effective leaders know when it's time to say goodbye.