What's wrong with American liberalism? What happened to the self-assured, optimistic, and practical Democratic Party of Franklin D. Roosevelt, Harry Truman, and John F. Kennedy? Why has Joe Lieberman, their closest contemporary incarnation, been run out of the party? How did anti-Americanism infect schools, the media, and Hollywood? And whence comes the liberal rage that conservatives like Ann Coulter, Jeff Jacoby, Michelle Malkin, and the Media Research Center have extensively documented?

In a tour de force, James Piereson of the Manhattan Institute offers an historical explanation both novel and convincing. His book, Camelot and the Cultural Revolution: How the Assassination of John F. Kennedy Shattered American Liberalism (Encounter), traces liberalism's slide into anti-Americanism back to the seemingly minor fact that Lee Harvey Oswald was neither a segregationist nor a cold warrior but a communist.

Here's what Piereson argues:

During the roughly forty years preceding the Kennedy assassination on November 22, 1963, progressivism/liberalism was the reigning and nearly only public philosophy; Kennedy, a tough and realistic centrist, came out of an effective tradition that aimed, and succeeded, in expanding democracy and the welfare state.

In contrast, Republicans like Dwight Eisenhower lacked an intellectual alternative to liberalism and so merely slowed it down. The conservative "Remnant" led by William F. Buckley, Jr. had virtually no impact on policy. The radical right, embodied by the John Birch Society, spewed illogical and ineffectual fanaticism.

Kennedy's assassination profoundly affected liberalism, Piereson explains, because Oswald, a New Left-style communist, murdered Kennedy to protect Fidel Castro's rule in Cuba from the president who, during the Cuban missile crisis of 1962, brandished America's military card. Kennedy, in brief, died because he was so tough in the cold war. Liberals resisted this fact because it contradicted their belief system and, instead, presented Kennedy as a victim of the radical right and a martyr for liberal causes.

This political phantasm required two audacious steps. The first applied to Oswald:

* Ignoring his communist outlook by characterizing him as an extreme rightist. Thus, New Orleans district attorney Jim Garrison asserted that "Oswald would have been more at home with Mein Kampf than Das Kapital."

* Reducing his role to insignificance by (1) theorizing about some sixteen other assassins or (2) spinning a giant conspiracy in which Oswald was a dupe of the mafia, the Ku Klux Klan, anti-Castro Cubans, White Russians, Texas oil millionaires, international bankers, the CIA, the FBI, the military-industrial complex, the generals, or Kennedy's successor, Lyndon Johnson.

With Oswald nearly deleted from the narrative, or even turned into a scapegoat, the ruling establishment – Johnson, Jacqueline Kennedy, J. Edgar Hoover, and many others – proceeded to take a second, astonishing step. They blamed the assassination not on Oswald the communist but on the American people, and the radical right in particular, accusing them of killing Kennedy for his being too soft in the cold war or too accommodating to civil rights for American blacks. Here are just four of the examples Piereson cites documenting that wild distortion: Continued...