“John Lennon represented life, and Mr. Nixon and Mr. Bush represent death.” So says Gore Vidal, succinctly, in one of the many testimonials by friends and ex-foes to the former Beatle in The U.S. vs. John Lennon, which traces Lennon’s life from lonely, rebellious orphan to international teenbeat idol to politically engaged fist raiser to cross-generational cultural emblem. Outwardly focused on the American government’s persecution and attempted deportation of Lennon and his partner, Yoko Ono, for countercultural activities deemed dangerous by the Nixon administration, David Leaf and John Scheinfeld’s documentary/love letter comes at a time when parallels to current affairs would seem obvious.

Leaf and Scheinfeld draw these parallels in a series of scenes that highlight Lennon’s performances at political rallies and at contentious or fawning press conferences. It’s a high-sheen, fast-moving work, which has the look, feel and sound of the VH1 broadcast it will, in fact, be in tandem with in its theatrical release. Produced with the blessing of Ono (who gave the filmmakers access to previously unseen archival footage and photos), and illustrating in vivid pictorial the remarkable detective work of Jon Wiener’s book Gimme Some Truth: The John Lennon FBI Files, The U.S. vs. John Lennon is a gripping and moving homage that brings in some new-old faces to flank the usual suspects in telling the story of Lennon and his badgering by the FBI: Mario Cuomo, George McGovern, John Dean, Walter Cronkite, G. Gordon Liddy and Geraldo Rivera.

The film opens with scenes from the 1971 benefit in Ann Arbor, Michigan, for political activist John Sinclair, who’d been sentenced to 10 years in state prison for selling two marijuana cigarettes to an undercover agent. Lennon’s appearance at the concert, alongside Black Panther Bobby Seale and poet Allen Ginsberg, was monitored by the FBI, which knew the event would draw wide attention to the Sinclair case and had planted informants in the audience. Lennon chose the event as a warm-up for a proposed whistle-stop concert tour that would follow the Nixon campaign nationwide and mix music with anti-war demonstrations. The FBI’s Lennon files detail the Nixon administration’s attempts to prevent the tour from happening and to put Lennon further out of Nixon-harming way.

As a record of the intermingling of rock music with anti-war and civil rights activism in the late ’60s and early ’70s, the film retreads a lot of ground that’s been detailed before, particularly in Andrew Solt’s 1988 documentary Imagine: John Lennon, which similarly attempted to convey the complexities of a man seriously engaged with the political and cultural tumult of his times yet increasingly conscious of his limited ability, as an artist, to effect change.

The U.S. vs. John Lennon propagandizes somewhat by zeroing in on the open pores and shiny pates of the baddies and isolating the colorfully tailored and lovable goodness of our hero. We see, for example, a clip of Nixon telling a big whopper about the withdrawal of troops in Southeast Asia, wiping the sweat from his upper lip.

It was Lennon’s engaging drollery and sense of the absurd that made his forays into political action to most of our liking, and often seemed like the only available human alternative to the cold proclamations of the more rigidly revolutionary types who regarded him as a mere wealthy rock boy playing at grown-up politics. And then there were those in the ostensibly progressive-minded media establishment who viewed Lennon as nothing more than a lightweight bigmouth with his head in the clouds. On that last score, The U.S. vs. John Lennon offers up the singer’s famous, filmed confrontation with the ludicrously snotty New York Times writer Gloria Emerson, who calls Lennon “dear boy” as he attempts to defend the role of the artist in political discourse.

When asked by a reporter why he was always in trouble, Lennon preferred a response like “I just have one of those faces, y’know, people never liked me face.” Repeatedly, he shed humorous human light on his politics, a stance that often made him appear deceptively naive about his own real political significance. That was the supposition of single-minded idealists such as Jerry Rubin and Abbie Hoffman, who, without informing Lennon, advertised his appearance at a rally outside the Republican convention in Miami in 1972, in which Lennon then refused to participate.

Lennon said, “Our society is run by insane people for insane objectives, so I’m liable to be put away as insane for saying that.” But he wasn’t put away. He was vindicated, his case played a major part in Nixon’s eventual resignation, and we’re all a little bit transformed if for that reason alone. The world’s a bigger mess than it’s ever been, but it’s a better mess, and we have dreamers like John Lennon to thank for that.

THE U.S. VS. JOHN LENNON ( * * * )

Directed by David Leaf and John Scheinfeld. • Starring John Lennon, Yoko Ono and Walter Cronkite. • PG-13, 96 min. • At the Osio Cinemas.