With gridlock and a contentious presidential election sucking up oxygen in Washington, ambitious politicians are looking west. Targeting the American movie business’s subservience to China and Netflix’s purchase of the icky, squicky coming-of-age movie “Cuties,” lawmakers sense opportunity in battles with entertainment industry titans. If they want to succeed, they’ll need to heed the lessons of previous throwdowns between Hollywood and Capitol Hill.

Congress has a long and storied history of inserting itself into the affairs of the entertainment industry, and recent years have given lawmakers plenty of targets.

A bipartisan coalition has voiced concern about China’s influence on the entertainment industry. Sen. Ted Cruz (R-Tex.) introduced legislation aimed at curbing Pentagon support for studios that censor films at the behest of Chinese officials, who control access to a very powerful market. The bipartisan Congressional-Executive Commission on China recently asked Disney honcho Bob Chapek for more information on the decision to film parts of “Mulan” in Xinjiang, the site of concentration camps where the Chinese government has detained members of the country’s Uighur minority. Meanwhile, Sen. Josh Hawley (R-Mo.) has called for Netflix to strip “Cuties” from its catalog, and Sen. Kelly Loeffler (R-Ga.) has suggested that hearings might be necessary after the movie was criticized as child pornography.

These contemporary lawmakers are part of a long tradition. The House Un-American Activities Committee held hearings in the 1940s and ’50s resulting in the blacklisting of writers who refused to testify about their membership in the Communist Party. Future second lady Tipper Gore squared off against John Denver about popular music in the ’80s. And more recently, lawmakers have probed Hollywood’s commitment to diversity and gender equality.

One classic dust-up occurred in September 1941. In his new book “Hollywood Hates Hitler! Jew-Baiting, Anti-Nazism, and the Senate Investigation into Warmongering in Motion Pictures,” University of Wisconsin-Milwaukee professor Chris Yogerst highlights the efforts of one Senate subcommittee to prove that Hollywood was sending the United States down the path to war.

Isolationist senators led by Gerald Nye (R-N.D.) hoped to demonstrate that Hollywood moguls such as Harry Warner, Nicholas Schenck, Louis B. Mayer and Darryl Zanuck were, due to their Jewish heritage and their ties to Europe, using their influence to encourage the United States’ entry into another global conflict. The resulting hearings were something of a disaster for the isolationists, who demonstrated that they were utterly ignorant not only of the business they were trying to micromanage but also the very films that they claimed were horrifying pro-war propaganda.

If politicians insist upon holding hearings now regarding current moviemaking controversies, there are a few things today’s senators could learn from Yogerst’s book.

The first, simply, is to watch the movies you’re holding hearings on before holding hearings on them. When asked by Sen. Ernest McFarland (D-Ariz.) to tell the committee what, exactly, was so dangerously propagandistic about the movies these moguls were making, Nye demurred, saying that they had “a spirit of hate that was engendered toward a race of people.” McFarland responded as any frustrated teacher might, noting that this was a conclusion, not evidence. What followed was a rather hilarious back-and-forth during which McFarland asked Nye if he’d seen “Flight Command,” “That Hamilton Woman,” “Man Hunt,” or “Sergeant York.” Nye’s responses, in order?

“I do not believe I did. … I did not see that. … I think not. … I think not.”

The Hollywood Reporter headline about that day’s testimony about summed it up: “SENATE INVESTIGATION A JOKE: Nye Holds Floor All Day—Talks Lot, Proves Nothing; Can’t Point Out Propaganda.” The lesson, then as now, is simple: If you’re going to condemn a work of art, watch it so you know what, precisely, you’re condemning.

A second tip might be to understand the actual business of filmmaking before going after the filmmakers. In the case of Hollywood’s dealings in 1941, that would have involved understanding which foreign markets provided what share of revenue.

“Nye had assumed that Hollywood’s interest was in defending Britain to ensure their exhibition profits overseas,” Yogerst writes. “[Wendell] Willkie pointed out that if economics were the industry’s only interest, it would be beneficial to work with the Nazis instead of opposing them.” In other words: Understand what is in Hollywood’s interest and how to ensure you can help, or stop, it from getting what it wants.

Which brings me to my third and final suggestion: Have a goal. One undercurrent of Yogerst’s book is that the Senate subcommittee convened by Nye wasn’t sure exactly what it wanted. Members were quick to decry claims that they were advocates of censorship, understanding that this was a losing battle; by the end of the hearing there was some talk of antitrust regulation aimed at lessening the power of the moguls. But there did not seem to be a real coherent strategy headed into the event, which helps explain the resulting mess.

Today’s lawmakers should think hard about what they want, beyond merely scoring political points at Hollywood’s expense. Otherwise, they may end up characters in the story they hoped to write — and the roles won’t be so flattering.

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