John Lennon would have been 66 this year if he hadn't been shot. As Yoko Ono points out in The US versus John Lennon and as this new feature documentary on Lennon's years as prominent anti-war activist goes to show, his memory is still very much alive.

A slick composite of Lennon's archived public appearances, intermingled with current interviews from figures from the Vietnam War era, this captures the evolution of Lennon from the edgiest of the Beatles to celebrity campaigner for Peace and Love. That's both its strength and its weakness. Iconoclasts will roll their eyes at its cosy, rose-tinted nostalgia, while fans will lap up the right-on, idealistic vibe.

The film catches up with Lennon as he is drifting away from the Beatles and beginning to use his celebrityhood and that cocky Liverpudlian wit to raise awareness about the wrongness of the war in Vietnam. There are the Bed-ins for peace and the first recording of anti-war anthem Give Peace a Chance in Montreal. We also see half a million demonstrators singing Give Peace a Chance in Washington DC, as well as concerts and television interviews.

As he became more involved with the peace movement, hanging with what the government considered dangerous political activists in New York, such as Abbie Hoffman, Jerry Rubin and Black Panther leader Bobby Seale, it becomes more sinister. We learn from apparently remorseful former CIA agents how they spied on Lennon and tapped his phones. (And they said he was being paranoid.) With Lennon's own songs providing a constant soundtrack to his life, the story then details how the Nixon government, fearing Lennon's influence during the 1972 election campaign, snarled both himself and Ono in a protracted deportation battle.

Would John have approved of the way his celebrityhood is used here? He'd probably be disappointed at the lack of bite. The flashy treatment of the archival material, like the Seventies styled animations that bring flat black-and-white photos to life add a good deal of zestiness. But there's something just a bit too packaged about the film. It's an uplifting and sometimes amusing take on the Lennon myth, but it also feels mellowed by history.

Gore Vidal draws a parallel between "dirty Dicky" and the current Bush/Cheney regime in blunt terms, but generally The US versus John Lennon takes a safe retrospective tone. Those looking for a rounded, warts 'n' all appreciation of the man or even a fresh take on Lennon's achievements will find the film lacking.