Workers remove a poster-banner for "The Interview" from a billboard in Hollywood, California, December 18, 2014 a day after Sony announced was cancelling the movie's Christmas release due to a terrorist threat. (Robyn Beck/AFP/Getty Images)

Now that U.S. intelligence officials believe that North Korea was behind the cyberattack on Sony Pictures Entertainment, the discussion has finally moved away from e-mails about Angelina Jolie to the real story, which is far more troubling. One of the nastiest regimes in the world effectively threatened to launch terrorist attacks in the United States if an artistic work was shown publicly. And, stunningly, almost everyone involved has caved.

Imagine that the Iranian government had threatened a terrorist attack on U.S. soil if, say, a book were about to be released that parodied its supreme leader. Would we not regard this as an intolerable surrender to threats of terrorism and a violation of core principles such as freedom of speech? In fact, a somewhat similar situation did arise in the fatwa pronounced by Ayatollah Ruhollah Khomeini on Salman Rushdie because of the author’s 1988 book “The Satanic Verses.” And much of the free world — although certainly not all — defended Rushdie’s right to write a satirical, even inflammatory, book about Islam and its prophet.

Yet when faced with the Sony movie “The Interview,” the reaction has been much different. After the largest U.S. theater chains said they would delay the film’s opening, Sony announced that it would officially cancel the Dec. 25 release. Other movie studios did not rally behind Sony. (In fact, Deadline magazine reported Wednesday that another movie set in North Korea, a thriller starring Steve Carell, had been canceled.) The stars of “The Interview” canceled their media appearances.

It could be said that this movie is just a comedy. But Charlie Chaplin’s “The Great Dictator” was also a comedy satirizing an evil maniac, Adolf Hitler. And it is worth remembering that, when Chaplin’s movie was being made in the late 1930s, Neville Chamberlain’s government wanted to ban its distribution in Britain in service of its policy of appeasement toward Nazi Germany. By the time the movie was released in 1940, Britain was at war with Germany, and everything had changed.

Why does a terrorist threat from North Korea produce appeasement, whereas threats from Islamic terrorists produce courage, defiance and resilience? I suspect it’s because we are fully aware of the barbarism of jihadi terrorists. But we tend to think of North Korea in somewhat comical terms — the odd dictators with their strange haircuts; the weird, synchronized mass adulation in stadiums; the retro-propaganda and rhetoric.

In fact, North Korea is one of the world’s most repressive and brutal dictatorships. Estimates are that it abducted thousands of people from neighboring countries following the Korean War, allowed 1 million to 2 million of its own people to starve in a famine in the 1990s and currently imprisons about 100,000 people in labor camps. The United Nations appointed a panel to investigate the human rights situation in North Korea; its report, released in February, paints a picture of a regime that has no parallel in the scale of its systematic cruelty and oppression.

The challenge that movie studios and theaters face is real because they have to balance freedom of expression with safety and commerce. But they have made a mistake. I understand it well. In 2009, Yale University Press published a book on the Danish cartoon controversy but refrained from publishing the actual — offending — cartoons (of the prophet Muhammad) because of fears of retaliation and violence. As a trustee of the university, I was asked to defend the decision (one I would not have made). Swayed by my concerns for an institution I love deeply and a group of administrators I respect greatly, I made a statement supporting the university’s actions that I have always deeply regretted. The right response then and now must be to affirm freedom of expression.

The U.S. government has to find a way to respond to this act of aggression on American territory. If not, North Korea will have gotten away with its worst cyberattack to date, as well as the most brazen threat of terrorism in recent times. In its triumph, it will be emboldened. And surely groups such as al-Qaeda and the Islamic State will note that the way to scare countries into submission is to threaten these very kinds of attacks. At that point, the story will be about much more than a Hollywood comedy.

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