Through it all, he stays in character — the "Stephen Colbert" character — with only a twinkle in his eye to let his audience know HE knows that most of what he utters is purposely dimwitted or wrong. He wrings larger meaning from nearly everything he does, illuminating it with self-contained mockery.
For nearly two decades, he has not only sustained but fortified this identity, giving it a full-bodied life of its own. It's quite an act.
Now he's decided to move on. (Comedy Central said he'll end "The Colbert Report" in eight months.)
Stewart voiced congratulations on Thursday's "The Daily Show": "The exciting news today is, I no longer need a cable subscription for the privilege of watching Stephen Colbert."
In a statement, Letterman endorsed him: "I'm very excited for him, and I'm flattered that CBS chose him. I also happen to know they wanted another guy with glasses."
Then on his show, Colbert reciprocated, saying Letterman "has influenced every host who came after him, and even a few who came before him — he's THAT good.
"And I gotta tell you," Colbert added, drawing cheers and applause, "I do not envy whoever they try to put in that chair."
But Colbert Nation can be pardoned for greeting the news with a measure of sadness. The Comedy Central show that Colbert masterminded is not only unique among current TV fare, but is likely unique in television history. In exchange, he is casting his lot with a 60-year-old desk-and-couch genre whose conventions its hosts defy at their peril. (Arguably the last attempt to revolutionize the late-night-talk hour was "The Wilton North Report" on Fox in 1987, which was absolutely terrible and flared out in less than a month).
Some will carp that Colbert is yet another white male with a hosting job.