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Sometimes I wonder why anyone would want to be president of the United States.

I know there are a lot of cool things that come with the job — a very easy commute, a very cool plane and never having to worry about traffic — but looking at President Bush today — and I mean this with the greatest of respect — it just struck me again: the guy is aging.

I've seen him up close over these years, interviewed him a number of times, sat in meetings with him several times and each time, noticing him getting a little older but somehow a lot faster than me. It comes with the job, I guess.

I remember thinking the same thing about Bill Clinton. Night and day covering him as a young Arkansas governor running for president, then interviewing him in his final year as president, you'd think he had aged 20 years.

Ditto, Jimmy Carter, who looked like he had the weight of the world on his shoulders leaving office. He did.

They all did — Republican, Democrat, the same thing. The job just takes it out of you — all those critics, all those jokes, all those barbs and all those worries. I suspect a lot of it has to do with the very real threats they see every day, the stuff we'll never know, the plots we'll never hear. Good thing because we'd age pretty fast ourselves.

There's a reason why they call former presidents a unique club. They know what it's like to lead. And they know what it's like to age.

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