A long-touted motion picture on prominent Hollywood screenwriter and communist Dalton Trumbo debuts in theaters this weekend. I will see the film, but first I’d like to share some background on Trumbo. I do so not as a film critic but as a historian of the Cold War and communism, including the Hollywood front for which Trumbo was extremely active.

For starters, it’s crucial to keep in mind that communism was responsible for the deaths of over 100 million people in the last century, double the combined tolls of World War I and II. It’s also vital to know that most American communists (small “c”) did not actually join the Party. Only the hardcore went that far. Those who joined the Party took a major leap of faith. They became loyal Soviet patriots. Regardless of their American citizenship, Communist Party members in the Stalin era (when Dalton Trumbo joined the Party) swore an oath: “I pledge myself to rally the masses to defend the Soviet Union…. I pledge myself to remain at all times a vigilant and firm defender of the Leninist line of the Party, the only line that ensures the triumph of Soviet Power in the United States.”

They wanted the “triumph” of Soviet power in America. They truly took marching orders from the Kremlin. The most fanatical among them (Trumbo included) remained in the Party even after the signing of the Hitler-Stalin Pact that launched World War II. Stalin aided and abetted Hitler in that apocalyptic action, enabling history’s deadliest war and the Holocaust.

American members of the Communist Party were dedicated to what their General Secretary William Z. Foster called a “Soviet America,” or what Langston Hughes called a “U.S.S.A.” “Put one more ‘S’ in the USA to make it Soviet,” proclaimed Hughes. “The USA when we take control will be the USSA.”

As for the Hollywood Ten, all were members of the Communist Party, and we’ve known their card numbers since the 1940s: Dalton Trumbo: 47187; John Howard Lawson: 47275; Albert Maltz: 47196; Alvah Bessie: 47279; Samuel Ornitz: 47181; Herbert Biberman: 47267; Edward Dmytryk: 46859; Adrian Scott: 47200; Ring Lardner Jr.: 47180; and Lester Cole: 47226. Most remained vigorous in their Party work right up until they were called before Congress — i.e., the bipartisan Democrats and Republicans today tarred with the dread label “HUAC.” Some, such as Alvah Bessie, traveled abroad and took up arms for the communists in wartime. The only one who repented was Dmytryk.

What about their work in film?

Communists knew that the film industry could be a tremendous source of propaganda. Vladimir Lenin said that “of all the arts, for us the most important is cinema.” Grigori Zinoviev, head of the Soviet Comintern, ordered that motion pictures “must become a mighty weapon of communist propaganda and for the enlightening of the widest working masses.” In March 1928, the Soviets held their first Party Conference on Cinema.

The Bolsheviks realized that nowhere was the movie industry as advanced and influential as the United States, especially in Hollywood’s Golden Age. Their American comrades wholeheartedly agreed.

Dalton Trumbo declared that “every screenwriter worth his salt wages the battle in his own way — a kind of literary guerrilla warfare.” He said that not employing the medium of film was “tantamount to abandoning the struggle altogether.”

A fellow screenwriter who militantly enforced that warfare was a nasty individual named John Howard Lawson, known as “Hollywood’s commissar.” In his Film in the Battle of Ideas, published by the communist house Masses & Mainstream, Lawson shrewdly instructed his comrades: “As a writer do not try to write an entire Communist picture, [but] try to get five minutes of communist doctrine, five minutes of the party line in every script that you write.” He insisted: “It is your duty to further the class struggle by your performance.”

As for Dalton Trumbo, he wrote some good movie scripts. He also wrote some that clearly echoed elements of the Party line. The trailer for the Trumbo movie shows him stoically meeting with Kirk Douglas for the classic film “Spartacus.” Here’s something you should know about “Spartacus:” For the film adaptation, Trumbo wrote a script based on Howard Fast’s novel, Spartacus. Fast was the proud recipient of the Stalin Prize.

Given such realities, Congress in October 1947 summoned Trumbo and Lawson and other screenwriters to ask about their use of film as covert propaganda. Congressmen had questions about the screenwriters’ Soviet loyalties and whether these loyalties affected what they were writing for mass consumption. In response, these secret Party members screamed foul and wrapped themselves in a First Amendment that did not exist in the USSR and would be the first thing facing the firing squad in a Moscow-controlled “Soviet America.” Rather than truthfully answer questions or try to persuade the public that their loyalties were to America and there was nothing to worry about, they denounced the congressmen, comparing them to Nazis.

“You are using the old technique, which was used in Hitler’s Germany,” shouted Lawson. The congressmen, said the dedicated Stalinist, were “trying to introduce fascism in this country.”

As for Trumbo, he held nothing back. “You have produced a capital city on the eve of its Reichstag fire,” he lectured the congressmen. “For those who remember German history in the autumn of 1932 there is the smell of smoke in this very room.” Trumbo was venomous in unhesitatingly torching his opponents as “Nazis.” He wailed as he left the hearing room: “This is the beginning of an American concentration camp!”

The irony here was amazing and tragic. Consider: at that very moment the Soviets — who Dalton Trumbo was pledged to — were actually taking over Buchenwald from the Nazis and making it their own concentration camp.

But the irony was worse. Trumbo was prolific in numerous communist fronts, including the pernicious American Peace Mobilization, which Congress identified as “one of the most seditious organizations which ever operated in the United States” and “one of the most notorious and blatantly communist fronts ever organized.” Founded in 1940, the group’s objective was to keep America completely out of the war against Hitler, including no Lend-Lease aid to Britain as it was being savaged by Hitler’s war machine. Why? Because Hitler, at that point, was allied with Stalin. And for American Communist Party members, any ally of Stalin had to be their ally, period.

Because of this (and more) the likes of Allan Ryskind, historian of the blacklist and son of the late screenwriter Morrie Ryskind, has called Trumbo “Hitler’s Enabler.”

Much more could be said here. It took Congress pages to cover Dalton Trumbo’s communist work. My article cannot do justice to his prodigious efforts, from being pro-North Korea during the Korean War to anti-Churchill when the prime minister delivered his “Iron Curtain” speech. And after all of it, doing virtually whatever the Communist Party asked, Trumbo said he “never regretted” joining. “As a matter of fact,” he told biographer Bruce Cook, “it’s possible to say I would have regretted not having done it.”

That is the truth about Dalton Trumbo. Please take it with you into the theater.

This article first appeared at Investor’s Business Daily.