Written, directed and produced by Michael Moore.

This is a very important documentary that should be compulsory viewing for every American citizen. Michael Moore, the idiosyncratic cross-media satirist has come up with a wake-up call for a country out of control, paralysed by fear, obsessed by violence. His subject is gun control, that peculiarly American oxymoron. Moore's method here as before is a personal statement, he doesn't strive for the impossible dream of objectivity. This is deeply subjective and all the more powerful for that.

As the title suggests, he takes as his starting point the horrific shooting at Columbine High in Colorado where 12 students and one teacher were killed and many more were badly injured by two disaffected youths armed to the teeth. He interviews staff at the school, shows CCTV footage of the massacre taken in the school canteen and brings two of the survivors to K-Mart to demand that bullets no longer be sold there. One of the shooters grew up on an army base outside Moore's own hometown of Flint, Michigan. This was also the town where the shooting of six-year-old Kayla Rolland by a six-year-old boy in her kindergarten class occurred.

Moore, a lifelong member of the National Rifle Association is angry and self-righteous about the proliferation of guns in American society, but he remains open all the time to different views on the issue. He has not come to a conclusion and then made a film to back it up. Using humorous anecdotes and animation, he places the issue in a historical context. He mentions white slave owners in the South arming themselves for fear that the slaves would revolt, the mythology of the gun built up around pioneer days in the Old West and sketches the NRA's early links with the Ku Klux Klan. He interviews members of the Michigan militia, men who consider it irresponsible not to arm yourself and train for combat to protect your family.

He broadens the scope of his investigation to include America's aggression as a nation through a montage of every post-WWII illegal invasion and coup d'état engineered by the US government through the CIA. This may have been added as a response to September 11th, which makes this ambitious work all the more timely and desperately needed. He also talks to James Nichols, Timothy McVeigh's Oklahoma bombing partner-in-crime. Finally he interviews Charlton Heston, the movie icon head of the NRA, who displays massive arrogance in justifying the holding of rallies in both areas days after the Columbine and Flint tragedies. He is skilfully caught out by Moore betraying some shockingly racist views as to the reasons for the US murder rate.

It is more shocking that Moore was able to elicit such a response from Heston, than it is that a white Hollywood star in his seventies, who is head of an ultra Republican gun lobby organisation would be a racist. This ageing movie star may seem like a soft target, but he still wields substantial power in an organisation that is a large White House funder.

Oh, did I mention it's also one of the funniest films you'll see all year? A healthy dose of black humour is needed to comprehend the pro-Second Amendment mindset that enshrines the civilian right to own and carry lethal firearms and this is what Moore excels at – the delicate balance between outrage and hilarity.

Nick McGinley