When a guy named Harvey Weinstein is suddenly fired from a company called the Weinstein Co., it should serve as a blaring alert to every powerful person in America who has preyed on less powerful people: Don’t think you can avoid the consequences.

If one of Hollywood’s biggest moguls is losing his position at the successful film studio he co-founded, no harasser is safe. If this sort of behavior can’t be ignored in an industry where the casting couch is a perennial cliché, no company that tolerates harassment is safe. The era in which superiors can freely subject those below them to unwanted advances or comments has ended. Those who don’t change will quickly become extinct.

In a statement, Weinstein admitted that “the way I’ve behaved with colleagues in the past has caused a lot of pain,” saying he came of age “when all the rules about behavior and workplaces were different.” Still, his lawyer said he “denies many of the accusations ...”

His reputation was no secret. In a 2012 episode of the NBC comedy “30 Rock,” a female character boasted, “I turned down intercourse with Harvey Weinstein on no less than three occasions ... out of five.” But until some of his accusers went public in a New York Times exposé last week, he was untouchable. Well, except by lawyers: The Weinstein Co. had paid settlements to at least eight women in response to accusations against him.

Will this be the scandal that finally forces abusers and their employers to realize they have to change? Maybe so. But there have been plenty of other cases that should have put them all on notice. Roger Ailes, who built Fox News into a colossus, was fired last year after some two dozen women came forward to accuse him of using his position to try to extract sexual favors. He was followed out the door by Fox News megastar Bill O’Reilly, ruined by credible allegations of similar conduct. Uber founder Travis Kalanick was forced out as CEO for allegedly tolerating a company culture of sexual harassment.

Weinstein had the power to make careers, and his accusers had much to lose by stepping forward. But he failed to grasp how the ground had shifted beneath him.

Another question:  Where on Earth was the board of directors? The settlements go back decades. In 2015, a memo from a woman accusing Weinstein of sexual harassment came to the attention of the company’s executives and directors. Some “were alarmed about the allegations,” the Times reported. “In the end, though, board members were assured there was no need to investigate.” Big mistake.

Directors there and elsewhere should be more vigilant going forward. Turning a blind eye to misconduct invites costly lawsuits and settlements for the companies they are supposed to be supervising. Board members can also be sued personally for such abuses.

Upholding standards and riding herd on behavior that can damage the corporation are a basic part of their responsibility as directors. These days, failure to fulfill that duty is something they are likely to come to regret. Several members of the Weinstein board resigned in the wake of this scandal. Directors at this company and others who have ignored such conduct should stop assuming sexual harassment can be covered up.