At once hilarious and sad, "Bowling for Columbine" examines a nation with millions of guns we all too frequently shoot at each other. Canada has a similar ratio of guns to people, but a tenth of our shooting deaths. What makes us kill so many more citizens than other developed nations? Moore, a jolly rabble-rouser, former shooting instructor, and lifelong NRA member, has moved on from his early fondness for guns, and here asks questions not easily answered, such as why our nation seems afraid and needs guns' false reassurance.

Moore documents TV news focusing on violence, ("If it bleeds, it leads"), and that although the American murder rate is down 20 percent, TV coverage of violent crime is up 600 percent. Moore returns several times to Columbine High, shows the massacre from security-camera footage, then introduces two wounded students who still have bullets in their bodies. The teenage Columbine killers bought all their bullets easily at K-Mart for 17 cents each. When Moore takes two victims to K-Mart headquarters to return the bullets for a refund, the unlucky K-Mart public relations people fidget and evade his merciless camera and questions until, on his third visit, K-Mart agrees to phase out selling ammunition. "We've won," says Moore, unbelieving. "This has never happened before." Comedian Rock suggests upping the cost of bullets; instead of 17 cents each, why not $5,000? "A lot fewer innocent bystanders would be shot," he suggests.

Moore finds Charlton Heston's home, rings his gate, and is invited in to talk. Although Heston recently announced he has Alzheimer's symptoms, this film shows no indication of that. Heston knows nothing of Moore, and answers his questions lamely. Why does he, living behind a gate in a protected neighborhood with security patrols, never himself threatened, need a loaded gun? Heston can't answer, nor whether he should have spoken at an NRA rally in Denver ten days after Columbine.

We have far too many guns, don't need them, and are shooting each other, all due to a national desire to be armed. ("If you're not armed, you're not responsible," a member of the Michigan militia says.) At one point, Moore visits a bank giving away guns to people who open new accounts. He asks a banker if it isn't dangerous to have all these guns in a bank? The bank, Moore learns, is a licensed gun dealership.