(Bloomberg View) —Revolutions come not all at once, but in tiptoe steps. Especially the bloodless ones, of course, but even rivers of blood will not convert the rest of the population instantly to the revolutionary’s command.

Just think how long it took for the United States to go from declaring that “All Men are Created Equal” to actually abolishing slavery. Or the back-and-forth dance of the early Bolsheviks before they decided to make war on all economic activity outside of the state.

Or consider how long it took 21st Century Fox Inc., the parent of Fox News, to decide that it was time to stop settling sexual-harassment suits and jettison their powerful targets. We have come a long way, legally and morally, since the days when people thought that men chasing secretaries around their desks made for a pretty funny joke. But it has taken us many decades to get to the point where even a powerful conservative media figure like Bill O’Reilly faces career-ending repercussions based on accusations of such behavior.

You might think it would have happened sooner, given that he seems to have been costing the company a lot of money in sexual-harassment settlements. But, of course, he was also generating lots of advertising dollars, thanks to a strong audience.

Given the age demographic of the average Fox News viewer, it’s safe to say that many of them remember the days when powerful men had a lot of leeway to do or say lewd things to lower-level female employees  — and judging from his ratings (which actually went up as the scandal unfolded), not all of them remember those days with horror. It may well have been the economically rational thing to do to keep paying off the lawsuits, and keeping the audience happy.

So what changed? Several things, actually, but before we get there, let’s go back for a moment and trace the history of sexual harassment in America. Contrary to somewhat popular belief, it wasn’t that everyone back in the bad old days thought that sexually harassing your employees was perfectly all right. It’s just that they had somewhat more nuanced views of these things than we do today. (Nota bene: “Nuanced” is not a synonym, or a code word, for “correct,” though it is often so misused by the commentariat.)

Old movies are full of young, handsome dudes engaging in relatively minor harassment, such as patting derrieres. They are certainly more tolerant of marital rape than we are. But they do not spend a lot of time celebrating men who demand sex in exchange for something a woman desperately needs, such as her job. Nor are they particularly tolerant of older and unattractive men who fondle their employees — bosses who at best come off with comic desperation, at worst as evil.

Roughly, the people of yesteryear thought that women might enjoy the attentions from very attractive men, but also understood that such attentions could be unwanted and abusive. And that probably reflects the beliefs of the larger culture, which might be summed up as “sexual harassment exists, and is wrong, but not all unsolicited advances are sexual harassment.” What we see in black and white, they saw in shades of gray.

In part because of this, they didn’t take it as seriously as we do. If you didn’t like sexual harassment, and your boss or your boss’s boss wouldn’t put a stop to it, you had a choice between putting up with it and looking for another job. The feminists of the 1970s changed that, by getting courts to declare that women who were sexually harassed had a legal cause of action against their firm. Companies were no longer allowed to care more about keeping the boss happy than keeping him from mauling the secretaries. And as firms grew wiser about the legal risks, they began to crack down.

Yet despite the legal risks, sexual harassment continued — I experienced it (from clients) as a young consultant in the 1990s. And, of course, all revolutions take longest to reach the top. Think of the Soviet party chiefs who were living remarkably like affluent capitalists, while the rest of their country lined up in empty supermarkets.

As long as sexual-harassment allegations were basically a legal problem, it made sense (economic if not moral) to subject it to cost-benefit calculation: Are the lawsuits going to cost me more or less than firing the accused harasser? In most cases, the answer is “yes.” But in the case of major producers in lucrative industries? It might be more profitable simply to assign a lawyer to their case and pay the plaintiffs to shut up.

But sexual harassment is no longer just a legal problem, because the law changed the culture. When the majority of managers are strictly forbidden to engage in that kind of behavior, it is exiled from the realm of “Something that unfortunately happens,” and banished to “Never Neverland.” Cultural tolerance for it erodes, and resentment from lower-level managers who have to play by the rules grows as the stars get the company to pay their lawsuits off for them.

And culture, in turn, informs both the economics of the decision, and the willingness of companies to subject those decisions to cost-benefit analysis. If management had received allegations that Bill O’Reilly was killing his staffers and stuffing their bodies in trunks, we can assume that Fox would not have been asking, “How much to make this go away?” And the more we regard these things as moral crimes, rather than “a series of unfortunate events,” the more costly it is when accusations come to light. According to CNN, more than 60 advertisers pulled out after the New York Times ran a story about O’Reilly’s history of accusations.

I think we may also be witnessing a transition, both in Fox News and the larger Rupert Murdoch empire. All innovative companies get to the point when they have to transition from the control of a dynamic founder to the next generation of talent, whether that is the children or a new CEO. When that happens, companies often become more “normal” in all ways — less of an outlier in both profits and behavior.

You can see this at Apple Inc., which still makes a fine product, but hasn’t given us a revolution along the lines of the iPod or the iPhone since the untimely death of Steve Jobs. And we may also be seeing it at the Murdoch empire. According to Gabriel Sherman of New York Magazine, “Late last week, the feeling inside the company was that Rupert Murdoch would prevail over his son James, who lobbied to jettison the embattled host.” Somehow, the tide turned, possibly because James’s brother Lachlan was persuaded (by his wife) that O’Reilly had to go.

The revolution is still not complete, and won’t be until the people in power don’t even remember a time when anyone was kept on board after multiple such accusations. Which is to say, we’re still a few generations off. But if we are not witnessing the beginning of the end, we are at least at the end of the beginning.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.