There's only one reason a man with a wife with incurable breast cancer and two small children at home should be running off to run for president.

Not because he wants the job, or even because she wants it for him.

Because she wants it for them.

Of course, the obvious explanation for why a man whose wife's cancer recurs would keep running is that he's too ambitious to give it up. After all, presidential candidates never see their wives anyway. Why let it interfere with a campaign that is going well enough? We're used to political marriages that put family second to ambition.

But I don't think that's it in John Edwards' case. First of all, it's not true. He was willing to give it up. Second of all, he didn't have to give it up forever, just for this time, against two very strong contenders no less.

The easiest thing for John Edwards the ambitious would-be president to do would be to go home and take care of his wife, and run in four or eight years as the sympathetic widower — or better yet, the husband of a survivor. At 53, he has time. It's what people would expect him to do, what many who know him expected him to do. It would serve his ambition just fine. The person it doesn't serve very well is Elizabeth.

This presidential campaign isn't just his dream, it's theirs. This may be the strongest marriage on public display in some time. My bet is, she convinced him.

The question facing John Edwards was easy because he has more chances, but Elizabeth Edwards faced a harder one. Do you give up the one chance you may ever have for the dream that was theirs because of cancer?

Cancer changes everything, as Leroy Sievers' wonderful blog for NPR, www.npr.org/blogs/mycancer, highlights every day.

But the ultimate challenge it poses is to keep living. I read Leroy's blog because the people there are so alive and so wise about the gift of life.

John and Elizabeth have a dream, and they're going for it. And why shouldn't they? Because cancer may limit her days? So they can go home and have everyone wait for her to die so her husband can get back to politics? Living with cancer is about living, not dying. It's a reason to go for it, not give up. To live more, not less.

At least that's my guess as to what she thought, what he thought, why they're going forward instead of going home. This is a stay-at-home mother making a stand for not staying home.

The question is: Will the country let them? Will they treat him as a candidate, or a man who should be home with his sick wife? Will they take her appeals as an endorsement of her husband's qualifications, or proof of his single-minded ambition?

At another time, it might have been different. But you'd be hard-pressed to find an American family that hasn't been touched by cancer, faced its own version of the Edwards saga. It's not just easy to relate, it's too easy. Even so, it all depends on what people think is really going on with John and Elizabeth; not so much how sick she is, but whether this is really what she wants and whether she can convince people of that.

In other words, it depends on Elizabeth Edwards, one of the smartest women I know. I don't blame John Edwards for not wanting to give up the chance to run for president with her by his side.

To find out more about Susan Estrich and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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