Al Gore can finally be grateful to look like a cigar-store Indian. It takes a straight face to argue so forcefully, as he does in “The Assault on Reason” (Penguin, 320 pages, $25.95), against the same irrational, cash-controlled, propaganda-driven politics that punched his ticket for years. Deriding the “manufacture of consent” enabled by advertising, he revisits a Senate campaign in which he authorized a clever “advertising buy,” then assures readers that he “was astonished when … [his] lead had increased by exactly 8.5 percent.” Golly!

It should be a case of “too little, too late,” but nobody minds. James Traub gushed in the New York Times that “Gore has attained what you can only call prophetic status; and he has done so by acting as he could not, or would not, as a candidate — saying precisely what he believes.” Mr. Gore’s “inconvenient truth” in this book, of course, is that those in charge won’t admit they’re smogging skies, chiseling away individual rights, waging senseless war, and, most significantly, burking the “public forum.” For all his vaunted hatred of propaganda, Mr. Gore is confident in his own Big Lie, that he’d treat that public with the respect it deserves.

He even confesses to his own uses of propaganda. He’s seen “many historical examples of vivid imagery producing vicarious traumatization that had been used for positive purposes.” He’s “learned that visual images … communicate information about the climate crisis at a level deeper than words alone could convey.” So manipulation is only as wicked as its outcome?

Let’s pretend that Mr. Gore didn’t, as he’s fond of reassuring his audiences, “used to be the next President of the United States.” Let’s pretend he just descended to Earth, an angel with a golden civics textbook: Would “The Assault on Reason” be any more convincing?

Yes and no. Much of what the book says is true but not original, and isn’t revisited with enough art or insight to justify it. Mr. Gore repeatedly relies on the old mantra that fear is the enemy of reason. Edmund Burke tells us on page 23 that “No passion so effectually robs the mind of all its powers … as fear.” On page 24, Lactantius appears: “Where fear is present, wisdom cannot be.” On page 25, Edward R. Murrow bellows, “We will not be driven by fear into an age of unreason.” (It’s a disappointing irony that a polemic against sound-bite politics should have relied so heavily on www.BrainyQuote.com.)

Mr. Gore is referring to the fear instilled by the war on terror. In the past, propaganda has certainly spurred fear, but fearing Jews for no good reason, to take an obvious example, isn’t the same as fearing well-financed terrorists whose stated aim is to wipe you out. Do Americans live in fear? To hear Mr. Gore tell it, you’d hardly think they have the attention span. It’s unclear, too, how the Bush administration can terrorize the public while reassuring it that everything’s just peachy.

“Demagoguery,” Mr. Gore writes, “means exploiting our fears for political gain.” Yet fear is far from the only emotion a demagogue can exploit. It’s easier and more effective to exploit the desire to be virtuous: That’s why Gore can captivate an audience by repeating in the dullest terms what many Americans already believe. As for his climate-change views — which are mercifully not the linchpin of this book — they often abdicate responsibility for Right Now by accepting the feather-light burden of pseudo-responsibility for Eons from Now. No wonder environmentalism is so often likened to a religion.

Like most good politicians, Mr. Gore has done plenty to make the world safe for the 30-second ad spot and the editorial cribbed from partisan talking points. Now he wants us to join him in gasping that “wealth and power have become concentrated in the hands of a few who consolidate and perpetuate their control at the expense of the many.” It’s a tough act to swallow.

It’s telling that he bemoans the collapse of periodicals and newspapers in the wake of television and the Internet. Newspapers are, in fact, every bit as one-sided as TV (despite a lot of wind-energy about “pamphlets” and “Common Sense”) and more so than the Internet (blogs receive only a few passing mentions), but Mr. Gore devotes plenty of column inches to pretending their demise is responsible for the impotence of public political engagement. Op-ed pages couldn’t for an instant withstand the massive machinery of cash and advertising that Mr. Gore takes so many disingenuous pages to “dismantle.” And he doesn’t give us a single persuasive example of what discourse or participation in a post-PR system might look like.

“The Assault on Reason” works on a more or less foolproof scheme: Tell the reader he’s being excluded from a dialogue. Present that “forbidden” dialogue in kindergarten-simple terms, heavy on appeals to authority and light on complex argumentation. The reader, thus flattered, will ignore contradictions and banalities that otherwise might insult his intelligence as the political process already does. With just a little luck, he’ll respond to the whole shebang in precisely the way the manufacturers of consent have planned it all along.

Mr. Beck last wrote for these pages on Dana Vachon’s novel “Mergers & Acquisitions.”