Michael Moore's Bowling for Columbine received a 15-minute standing ovation at the Cannes Film Festival (along with a special anniversary prize), and no wonder: It confirms everything the French and other Europeans despise about America. Moore's latest provocation is sometimes rickety in its logic, and never plays fair with the power elite, but it does raise an inescapable question: Why are we Americans so screwed up?

The trigger for that question, so to speak, is guns. America leads the world by a wide margin in shooting deaths, even though it shares many of the same theoretical root causes with much of the planet. Other countries also enjoy violent movies and videogames, have savage historical legacies, experience terrible poverty, and even report large numbers of gun-owners. So what's with all the carnage in the good old USA? Moore hasn't arrived at the definitive answer, but his theories are provocative and the question is vitally important to our survival as a civilization.

What makes America so gun-crazy, in Moore's view, is a unique combination of factors: a still-unresolved racial divide that continues to compel white suburbia to arm itself; a mass media whose "If it bleeds, it leads" mantra feeds a climate of fear; and a gun lobby that has taken "the right to bear arms" far beyond hunting and home security. Moore is himself a longtime member of the National Rifle Association (from the hunting days of his Michigan childhood), and he notes that in Canada, where seven out of every ten households keeps a gun, there are only about 160 shooting deaths a year (compared to over 11,000 in the U.S.) and no one locks the front door. Needless to say, probably very few of those guns are AK-47s.

Bowling for Columbine, which takes its title from the morning activity of misfit teens Dylan Klebold and Eric Harris on the day they massacred 12 students and one teacher at their Colorado high school, rambles all over the place in its quest for answers (or, rather, those that fit Moore's agenda). Like the increasingly rotund Moore himself, it's a pretty shapeless documentary, climaxing in two of the filmmaker's trademark confrontations. First, Moore brings two young Columbine victims (one paralyzed) to Kmart headquarters, and embarrasses the retail chain into halting its sale of bullets. Despite Moore's self-congratulatory smugness and the exploitation of the boys, it's a real, constructive achievement. Less satisfying is Moore's ambush of Charlton Heston at his home, as he tries to bully the NRA president into accepting blame for the tragic shooting death of a child back in Moore's hometown of Flint, Michigan.

Moore's black-and-white view of American history and society is a serious flaw, but Bowling for Columbine is often both raucously entertaining and deeply shocking (like much of this political gadfly's film, TV and print output). The film is most engaging whenever it zeroes in on the little absurdities of American gun culture: the bank that gives away free firearms with a new account; the metal-detector company video that shows a student removing an entire arsenal from underneath his baggy clothes; the teen napalm aficionado who broods over the fact that his high-school administration rated him only the number-two potential terror threat in his class. There's a lively, highly outspoken cartoon capsule history of American bloodshed narrated by a bullet, and an amusing sketch envisioning a spinoff of "Cops" devoted to white-collar offenders. But in his righteous anger, Moore often makes simplistic arguments, facilely connecting Columbine to the American bombing of Kosovo (which happened on the same day) and the presence of a Lockheed Martin military-weapons plant not far from the school. (TV producer Dick Clark also gets chastised by Moore for supporting a workfare program that indirectly led to an unsupervised child bringing a gun to school and killing a six-year-old classmate. Perhaps Clark's next project should be a psychic-hotline show.)

Bowling for Columbine is alternately thought-provoking and thoughtless, invigorating and infuriating. But at the very least, it does the valuable service of getting Americans talking beyond patriotic cant and clichs.

-Kevin Lally