NEW YORK — The new George Clooney movie Good Night, and Good Luck tells a classic American morality tale. Once there was a madman named Senator Joe McCarthy who spread fear of communism throughout the land until a dark-haired knight, CBS newsman Edward R. Murrow, brought him down.

The truth, historians say, is more complicated.

"I was pretty impressed by the movie, especially as Hollywood history goes, but the story is kind of claustrophobic and isolated. You get no sense of what was going on in the wider culture,'' says Thomas Doherty, author of Cold War, Cool Medium and a professor of American studies at Brandeis University.

Good Night and Good Luck, directed by Clooney and starring David Strathairn as Murrow, is a smoke-filled, black-and-white mood piece set mostly at CBS News headquarters. Much of the action centres on Murrow's famous 1954 newscast in which he used newsreel footage of McCarthy to cast the senator as a glowering demagogue.

What is in Good Night and Good Luck is essentially accurate, Doherty and others say. They note instead what the movie leaves out, from mention of journalists who had already stood up to McCarthy to signs that the senator was already on his way down.

McCarthy, a Wisconsin Republican, first received national attention in 1950 when he waved a piece of paper that claimed was a list of communist sympathizers in the U.S. State Department. The number of Communists changed in subsequent speeches, but the allegations remained, and caught on.

He was soon a cultural and political force, shouting down congressional witnesses and pounding his gavel, a first-term senator so powerful that in 1952 even Dwight Eisenhower, a military hero and Republican candidate for president who disliked McCarthy, hesitated to criticize him.

McCarthy did have media critics. Even the co-screenwriter of Good Night and Good Luck, Grant Heslov, has acknowledged that Murrow was not the first to challenge him. The Washington Post took him on, as did some of Murrow's CBS colleagues. Historians liken Murrow's role to that of Walter Cronkite's 1968 broadcast against the Vietnam War, a sign that the centre had turned.

"When Murrow goes after him, he's finished. That's when you know he's losing the public,'' says David Halberstam, who has written about McCarthy in The Fifties and The Powers That Be.

By the time Murrow attacked McCarthy, his influence already was declining. The Korean War ended in 1953, removing one source of anti-communist fever. Democrat Harry Truman was president when McCarthy entered the Senate. But by 1953, Eisenhower was in office, meaning that McCarthy's allegations of communism in the government were essentially an attack against his own party.

McCarthy still has defenders, including such conservatives as William F. Buckley and Patrick Buchanan. If the man was flawed, they say, his suspicions were sound. As declassified Soviet archives show, there was a vast communist spy ring, with many liberals now acknowledging that such Cold War figures as Alger Hiss and Julius Rosenberg were spies. One suspected communist defended by Murrow, his friend and former mentor Laurence Duggan, also turned out to be a Soviet agent.

But critics say McCarthy had nothing to do with catching Hiss or any other spies. Even in his lifetime he was regarded as an opportunist far better at targeting innocents -- liberal defenders of the New Deal -- than at uncovering the guilty.

David Oshinsky, a professor of history at the University of Texas at Austin and author of the McCarthy biography A Conspiracy So Great, says that most of the communist spies in the U.S. government had been uncovered by the late 1940s.

"All of these charges by McCarthy were a way of getting the Democrats out of power,'' Oshinsky says. "The Democrats had controlled the government for 20 years and the New Deal had helped a lot of people. So Republicans turned instead to saying that the Democrats were soft on communism, which was ridiculous.''

Historians note that anti-communism did not begin with McCarthy and did not end with him. Purging of suspected subversives in Hollywood began well before McCarthy's rise, as did the allegations against Hiss, the former aide to President Franklin D. Roosevelt. Truman instituted a government loyalty oath in 1947, when McCarthy was still little known outside Wisconsin.

While McCarthy's power quickly faded after the Murrow broadcast -- he was censured by the Senate in 1954 and died three years later -- McCarthyism went on. Only at the end of decade did Hollywood openly defy the anti-communist blacklist, when Dalton Trumbo was credited by name for his script for Spartacus. Only in the 1960s did the blacklist end on television.

"People associate him with anti-communism because of the media images,'' Doherty says. "He is vivid in our minds in a way that other characters aren't.''