A number of years back, there was a San Francisco mayor of whom it was said, “Three drinks and he thinks he’s invisible.”

He wasn’t.

Today, with the Internet and a camera in everyone’s pocket and a culture where people are willing to share their lives with the world in 140 characters or less, it’s hard to believe any politician can believe his peccadilloes will remain secret for long.

And then there’s Bob Filner. And Anthony Weiner. And all the other officeholders who go to bed at night thinking, “That will never happen to me.”

That may work for a while. Filner, by all reports, was a lout with women long before he became San Diego’s mayor last year. But while people may ignore the actions, however crass, of a backbench congressman, it’s different when you’re head of the eighth largest city in the country.

For those who are counting, seven women have now come out publicly to say they were pawed by Filner over the years and the phone at the sheriff’s harassment hotline is likely still ringing. The latest group includes a college dean, a retired Navy admiral and a pair of San Diego businesswomen.

Filner, who’s been in one political office or another since 1987, has to be the only politician in America who doesn’t realize he’s a dead man walking. On Thursday, for example, he called on the city to “take a deep breath” and allow time for a complete, impartial investigation of the complaints.

But in any political scandal, it’s the court of public opinion that makes the most important decision and in San Diego, that verdict is in. Even the local Democratic Party, which was beyond thrilled to see Filner win the mayor’s job, voted overwhelmingly Thursday night to show him to the exit.

Filner isn’t the first California politician to find himself caught up in a sex scandal and he won’t be the last. And not every politician pays a price for his missteps.

In 2007, for example, San Francisco Mayor Gavin Newsom admitted that he’d had an affair with the wife of one of his top aides. That didn’t stop him from being re-elected later that year or being elected lieutenant governor in 2010.

Los Angeles Mayor Antonio Villaraigosa, married 20 years, carried on a very public affair with a television reporter that was recounted in tabloids across the country. Yet he also managed to get re-elected and is being talked about as a future candidate for governor.

So why the furor over Filner? What’s different with his problems?

Well, the American people are a lot more willing to forgive passion than stupidity.

When someone like Newsom, Villaraigosa or former South Carolina Gov. Mark Sanford confesses that they’ve cheated on their wife or, in Newsom’s case, with someone else’s wife, people don’t like it, but they can understand it.

Even among men and women who would never dream of straying, there’s at least a touch of feeling that “there but for the grace of God go I.” When you listen to Sanford ramble on like a lovesick teenager about his Argentine “soul mate,” there has to be at least a thought of “What if …?”

But when it comes to putting women in headlocks and making lewd suggestions, cornering them in offices, groping them in elevators and suggesting they come to work without panties, not so much.

People are far more likely to echo the angry comments Rep. Nancy Pelosi made about Filner and Weiner (who definitely needs to have his cell phone taken away) at her weekly news conference Thursday.

“The conduct of some of these people that we are talking about here is reprehensible,” Pelosi said. “It is so disrespectful of women. And what is really stunning about it (is) they don’t even realize it.

“You know, they don’t have a clue … if they are clueless, get a clue. If they need therapy, do it in private.”

John Wildermuth is a longtime writer on California politics.

UPDATE: At a noon press conference Filner apologized for his behavior and said he was going into a behavior counseling clinic but did not resign.—editor