YOU CAN mock Jesus, insult Mohammed and meet Buddha on the road and kill him, but if you dare to question the genius of capitalism, you've really blasphemed. To say that capitalism's unregulated excesses create misery, waste and waves of uncertainty, to go fully on the offensive, as Michael Moore does in his collage-documentary Capitalism: A Love Story, you can expect loads of feedback.

The study begins more or less with Jimmy Carter: "Along came Debbie Downer," Moore says sarcastically. Carter's accurate forecast of debt and dependency on foreign oil caused him to be swept aside by cheery spokesman Ronald Reagan. Newly elected, Reagan spoke for Wall Street—today, Reagan's "We're going to let the bull loose" sounds as pregnant as Merian C. Cooper's promise to Fay Wray: "You shall have the tallest, darkest leading man in Hollywood."

Subsequent presidents didn't mess with the formula. Graphs here show what most will have already sussed out: since the Reagan-era tax cuts in the top percentiles, the urge to get rich by pumping the stock market through layoffs and increased working hours and productivity (but with wages gone stagnant) has flourished. Lastly, we have the ever-steady rise of debt as the submillionaire class filled the gap with credit cards.

It's been 20 years since Moore made Roger & Me about the layoffs that devastated Flint, Mich. The only thing that has changed is that Flint is worse, and its woes have spread throughout the United States. Moore makes a nationwide tour of today's wreckage. He follows the collapse of the real estate market and interviews a self-confessed "vulture" picking the bones of condos in Florida.

In Illinois, Moore sits with victims of a family-farm eviction. In upstate New York, he discusses airline companies squeezing pilots' wages, causing them to try everything from plasma selling to food stamps to make ends meet. Moore is never so dead-on as when observing the contrast between the public lionization of Chesley "Sully" Sullenberger III and the congressmembers who stayed away in droves when he testified about the frightful overworking of pilots. The film investigates the rise of "dead peasant" insurance policies, in which corporate employers try to make capital off deceased employees. Finally comes last year's bank bailout, conducted in secrecy and facilitated with the kind of fearmongering W and his team did best.

Some of the enmity against Moore arises because of his looks. As Jay told Silent Bob, no one wants to see a fat man cry. But wouldn't it be a wonderful world if wealth made you obese? It would be stirring to see on Market Watch a parade of Goldman Sachs spokesmen, Wall Street Journal commentators and Treasury Department secretaries who looked like they would have to be buried in piano crates. Still, when Moore does the faux-naive thing—standing outside the New York Stock Exchange with a bullhorn or trying to buttonhole executives to get them to explain the derivatives market—he's wasting our time and his. At this point in his career, it's irrelevant for him to pretend that he doesn't know more than we do. He's just using the time-honored "Michigan Defense," as seen in Anatomy of a Murder: "Your honor, I'm just a humble country journalist, doing the best I can against this brilliant system."

When Moore is at his best, it is not as defense lawyer but as prosecutor. And what's been worthwhile since 1989 is his tendency to sass back corporate spokesmen instead of taking their statements at face value. The man has a utopian vision, and this vision is lodged in his past: his father's 33 years at the GM plant provided a single income enough to pay off their house, send his kids to Catholic school and give him medical coverage and four weeks of vacation. When all of this was swept away through union-busting and plant closures, what, exactly, did Flint—what did any of us—get in return?

Moore has to dig into the past to see what a future might be like. He plucks out of the memory hole a little-remembered 1944 speech of Franklin Roosevelt proposing a second bill of rights for American citizens. The speech is a beautiful summing up of Moore's thesis, a calm balance to Moore's extremely good use of found-footage montage and borrowed soundtrack music.

The criticisms of Capitalism: A Love Story are obvious. It's one thing to note that the Italian constitution passed an equal-rights clause: in reality, has Italy vanquished sexism? The problem of the derivatives market deserves its own documentary—and has it, in new documentary American Casino. Naturally, Moore could have taken his cameras to walled enclaves and country clubs to prove that unregulated capitalism is the best of all possible worlds. Fox News et al. do a good job of finding svelte Republicans to remind us that racism is over, the recession is corrected and everything will be fine once Obama is run out of town. You could quote Baroness Thatcher's favorite comment on socialism—"Eventually, you run out of other people's money"—while neglecting to remember how Karl Marx wrote that this, precisely, was an essential problem of capitalism.

But Sicko energized the current debate over health care. Who knows what this documentary will touch off? Here, Moore opens a door that most of the powers that be would like to remain closed. This call for democratic socialism sounds loud, clear and not at all shrill after 30 bruising years of privatization, layoffs and shameless corporate thievery. Hugely entertaining, Capitalism: A Love Story will get people in touch with an anger they didn't know they possessed—and a hope they didn't dare let themselves feel.

CAPITALISM: A LOVE STORY (R; 127 min.), a documentary by Michael Moore, opens Oct. 2.

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