The global protest against the Iraq War on 15 February 2003 was a pivotal moment in recent history, the consequences of which have gone unreported. We Are Many chronicles the struggle to shift power from the old establishment to the new superpower that is global public opinion, through the prism of one historic day.

After background about the childhood and youth of John Lennon (1940-1980) and the birth of Vietnam-War protests, the film plunges into Lennon's quest for world peace: compositions such as "Give Peace a Chance", the lie-in following his marriage to Yoko Ono, appearances at concerts, "War Is Over" posters, and plans for a series of concerts in 1972 in U.S. presidential primary states reach newly-enfranchised young voters. This plan for concerts, in particular, led a prominent Senator, the FBI's J. Edgar Hoover, and Nixon's White House to initiate a concerted and illegal effort to deport Lennon. Thirty talking heads, led by Yoko, comment on Lennon and these events.