Stephen Colbert wants to impregnate you. And not just you: The host/main character of Comedy Central's Colbert Report says he has way too many opinions to fit onto a half-hour nightly show, "and right now, all that opinion is going to waste, like seed on barren ground.

"Well no more," Colbert continues in the introduction to his new book, I Am America (and So Can You!) . "It's time to impregnate America with my mind."

That bit of absurd braggadoccio, for those who are unfamiliar with the O'Reilly-ish blowhard persona Colbert (don't pronounce that T!) has perfected on his show, is a clue that what follows is satire aimed for—or rather at—the "social values" conservatives who keep the remote frozen on Fox News' hot-airheads and care more about teenagers having sex than about corporations screwing the rest of us. Colbert is the half-ironic, half-earnest figurehead of an army of devotees he calls Colbert Nation, and he made the Time 100 (and the personal heroes list of many) for his lacerating "tribute" to President Bush at last year's White House Correspondents' Dinner. I Am America is a gleeful reductio ad absurdum tour of Karl Rove's wedge issues, presented in the form of a high-school Social Studies textbook: Colbert provides the last word on religion ("Since the Bible is 100 percent the true Word of God, and the Jews believe in the Old Testament, that means Judaism is 50 percent right"); the media ("There are a few journalists who aren't sex offenders. Those people work for Fox News"); Iraq ("God won the War. He just doesn't occupy very well"); homosexuals ("If God were gay, he would have turned Adam's rib into Dermot Mulroney") and more—230 pages of more.

Don't be surprised if this sounds familiar. Just as The Colbert Report is an offshoot of The Daily Show with Jon Stewart , Colbert's book is best read as a companion volume to Stewart&Co.'s 2004 bestseller America (The Book): A Guide to Democracy Inaction . Both use a didactic textbook form to skewer the ignorance and apathy of Americans—their readers excepted. And ironic smugness aside, the Colbert Nation may actually have the informational edge: Surveys have shown that nearly a quarter of adults under 30 say they get their political news from comedy shows, and the adults who score highest in current-events knowledge are regular viewers of The Daily Show and The Colbert Report . By all rights they should be a disappointment to Colbert, the man who gave us "truthiness" (gut-checking instead of fact-checking).

I Am America is a sharp snickersnee of ironic engagement, but like Stewart's book, it's funniest and most effective when read only a few pages at a time; in long stretches, it tends to put the "tire" in satire. And satire is best enjoyed in small bites—the better to savor the bitter aftertaste.

I Am America (And So Can You!)

. Grand Central Publishing, 230 pages, $26.99.