The Importance of Being Stephen Colbert

After tonight, he's gone. No more will the Stephen Colbert with his Clark Kent hair, his merry gumdrop eyes protected by stern wire-rims, his body encased in a glisteningly smooth Brooks Brothers suit — no more will that Stephen Colbert roam America, telling it what to do with such authority, such assurance, such magnificent idiocy.

Tonight's the night Colbert inters The Colbert Report, burying it in the great Mausoleum of Television Past, somewhere to the right of Edward R. Murrow's grave and rubbing elbows, perhaps, with Dave Garroway's chimp J. Fred Muggs.

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Colbert has spent his final days being ultra-Colbertian: Wearing noise-canceling headphones playing Taylor Swift's "Shake It Off" so that he would not have to hear the details of the Congressional report on torture; outing himself as the artist Banksy; and telling guest Phil Klay, Iraq War vet and National Book Award winner, that he, Colbert, was proud to have "used the troops as a cudgel against people who disagreed with me."

Yes, it's been one long (nine years!) performance of unparalleled comic conviction. I would say that Colbert's achievement amounts to a sustained piece of performance art, but that's the kind of thing James Franco would say — in fact he did say it recently, so I don't want to say that. My own metaphor is that Colbert is a ventriloquist who used his own body as his dummy.

Pause and admire the persona that Colbert constructed and maintained with a scrupulous lunacy. Nine years ago, he set himself task of satirizing the blowtorch blowhardiness of Bill O'Reilly, who provided the anti-template upon which the comedian's show was built. The Colbert Report was the fun-house version of The O'Reilly Factor, Colbert's "Word" segment modeled on O'Reilly's "Talking Points Memo."

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But it wasn't enough to do a Fox News parody — not when there was so much aggressive fatuousness set loose all across the American landscape. And so the Colbert character became a bumptious interloper in all sorts of places. He established a Super PAC that raised millions of dollars to prove how easy and awful it is to exploit lax campaign-spending laws. He has invaded the worlds of insects and sugar, having both a species of spider and a species of Ben & Jerry's ice cream named after him. His greatest extracurricular activity will probably remain his devastating 2006 roast of President George W. Bush, and the entire Washington press corps, during that year's White House Correspondents' Dinner. (Listen and look at that performance. Those who understood what was going on sound as though they're choking on the fish course, shocked to discover the sharp bones of truthiness; those who didn't get it look dazed, as though hit on the head with a gigantic mallet.)

Colbert the wit, the enthusiast, used the Colbert character as a force for good, as in his interviews with Stephen Sondheim and Maurice Sendak, doubtless introducing millions of people to their work. Colbert's unalloyed pleasure at speaking with them was, you felt, his reward for doing such heroic work on a show dedicated to exposing lies, mendacity, obfuscation, and stupidity.

The exit of Stephen Colbert is probably unique in TV history. I can't think of any other performer who wasn't in a sitcom or a drama who has shed his self-created character to move on to a new career opportunity: being himself. Unless Pee-wee Herman had a post-playhouse talk show I'm not aware of, Colbert is ending as he began: a complete original, a revolutionary in a rep tie.

"I'm as happy as a pig in a candy store that allows pigs," he said on Tuesday night's show, fully in character. I wish him happiness and good luck as he ventures into the risky, frisky, fraught business of late-night-talk-show hosting. He'll have to succeed without the benefit of a Colbert Bump.