David Letterman's uncomfortable situation has been his success

LOS ANGELES — David Letterman celebrates 30 years in post-prime-time television this week, spent first as the host of "Late Night With David Letterman" on NBC and then, since 1993, of "Late Show With David Letterman" on CBS.

He went to CBS, famously, after NBC gave "The Tonight Show" to Jay Leno, despite an endorsement for Letterman from its departing host, Johnny Carson (who in his retirement would also sometimes supply him with jokes). It was a bitter pill that still produces the odd quip from Letterman, nearly two decades later.

Carson's "The Tonight Show" was an institution — Leno's, not so much — but it wasn't a bad thing for Letterman to lose that war. The underdog status suits him; it allows him to position himself as an outsider, in show business but not exactly of it. (I speak relatively, of course, of a man whose 2011 earnings, from show business, Forbes estimates at $45 million, but every dog has his context.)

Leno, his time-slot competitor, reliably draws more viewers, but Letterman has created a community, partly from having remained in New York: Right outside the theater doors, mad, bad, beleaguered and attacked, the city reflects "Late Show" as "Late Show" seems to speak for it.

The self-deprecation is, of course, also a kind of misdirection (and an inheritance from Carson, who perfected the art of getting a laugh on the back of an unfunny gag). Letterman is one of the great figures of television; It is his natural medium, both in the sense of an art he practices and the element in which he swims. He rules his turf; there is no desperation in his presentation; he does not need to impress you or the celebrities who sit next to him.

As the king of all he surveys, he can afford to be himself; he is comfortable enough to be seen as uncomfortable — to actually be uncomfortable — though even his worst real-life moments and most sincere apologies for misfiring jokes have a way of fueling more jokes. He controls the field in a way that leaves room for accidents and integrates them into the comedy.

Letterman turns 65 this year; it has been a dozen years since he underwent a quintuple bypass, and he looks fit, if grayer and balder. But except to downplay his intelligence, he doesn't pretend to be other than he is. ("When I was your age I had a paper route," he told Lady Gaga recently.)