Charlie Gibson has just moved into the anchor desk on ABC's "World News Tonight," becoming Charles Gibson in the process but otherwise recognizably himself. Other anchors have kept their nicknames when they took the job: Tom Brokaw was never Thomas, nor Dan Rather Daniel, nor Bob Woodruff Robert, in his brief term. (Will Katie Couric be Katherine at CBS?).

But Gibson is running against the additional weight of his congenital boyishness, his regular-guy demeanor and an all-purpose cheerfulness burnished over nearly two decades in the daddy chair of "Good Morning America," which required him to seem terrifically interested in anything at all. He is a Princeton graduate who has interviewed presidents of the United States but looks like one of the junior Waltons.

The anointing of a network nightly news anchor is news itself if only because it happens so rarely: They are chosen less frequently than presidents — Peter Jennings was the ABC anchor for more than 20 years and would be there now if death hadn't intervened — and, indeed, of all jobs in television, it is the most presidential. The anchorperson stands not just for his particularly corporate nation state but for his constituents, his viewership — he represents them to the world, just as he represents the world to them. He must be a coolheaded voice of reason when all around, including actual presidents, are losing theirs — their cool, their heads, their reason — or a hurricane hits, or something blows up.

And like the presidency, it is not just a job you do, but a part you play. It's not to question the journalistic bona fides of Gibson or any of his colleagues to say that their hiring is first and foremost a casting decision, just as a TV news program is first and foremost a television show. At the same time, the part dignifies the actor: Some presidents were doubtless presidential in the cradle, just as some anchormen might have shaken rattles with precocious dignity, but in each case, the job bestows some kind of gravitas on the holder, although, as we have seen, it can't work miracles.

Gibson, who is hanging around "Good Morning America" through the end of June, has been doing double duty and has been equally convincing dealing with matters of war and with the money you can save using coupons in New York restaurants.

On some level, the choice seems counterintuitive: He's 63, nearly two decades older than the two anchors he's replaced — Bob Woodruff, recovering from a roadside bombing in Iraq, and Woodruff co-anchor Elizabeth Vargas, who could not hold the ratings and is leaving under cover of pregnancy. He's a mark of solidity in a time when the biggest question in TV news is how to create a new audience, not just hang on to the shards of the rapidly thinning old.

Since the anchorman proves his mettle and writes his legacy in extraordinary circumstances, those moments when he must think on his feet and feel for the nation, there's not much to say about Charlie yet. (He might be Charles in the credits, but he's still "Charlie" to the correspondents who address him from the field.) He isn't dashing like Jennings, or a flak-jacket reporter like Dan Rather (Woodruff — globe-trotting, multilingual, embedded — was a bit of both). One imagines he'd be a good dinner guest, that he wouldn't dominate the conversation, even though his stories would be better than anyone's, and that he'd help with the dishes afterward.

His signal quality, I think, is a kind of egolessness. One feels that he never coveted the job and that even now it's something he could walk away from. (And there does remain the question of what happens when Bob Woodruff gets better.) It's exactly the quality one wants in a president — and rarely gets.