THERE IS an unofficial rule in journalism that three makes a trend, which means that Mark Sanford (disgraced former governor, now a South Carolina congressman), Anthony Weiner (disgraced former congressman, now running for New York City mayor) and now Eliot Spitzer (disgraced former governor, now running for New York City comptroller) have made 2013 the year of the quick-return-to-politics-after-a-sex-scandal-that-was-supposed-to-end-your-career. Whether this phenomenon is new or not, we find it worrisome and a little sad.

It's not that we think that sex scandals should disqualify a person from holding public office. Actually, we suspect that within a decade or so, there will be no more personal scandals, because there won't be anyone left untainted by some indiscretion - a racy Twitter message, a drunken Facebook photo, a humiliating search history released to the public under sketchy circumstances involving the NSA or a big tech company.

It's not that we don't believe in second chances, either. Everyone needs them, most people deserve them and it's a beautiful thing about humans that we can be a forgiving bunch.

But two of these three men were involved in something worse than a sex scandal. Without explanation, Sanford disappeared for days from a state where he was the chief executive, responsible for dealing with emergencies and stuff. Spitzer engaged in activities for which he had aggressively prosecuted others and signed strict new laws about. In his own way, each violated the public trust. (Weiner, by contrast, was just an unimpressive congressman who is now seeking higher office.)

And yes, even people who violate the public trust can earn a second chance. But "earn" is the key word here, and what makes these eager returns to politics worrisome is that they threaten to make the public trust appear so cheap. If these politicians made meaningful philosophical changes to how they think about public service during their short time in the political wilderness, we haven't seen it. If they contributed to society in new ways, we haven't heard about them. Weiner hurried back to the campaign trail as fast as his legs could carry him. Spitzer and Sanford wandered a bit longer, but both spent a good deal of time listening to themselves talk on television in the interim.

The likely lesson for politicians everywhere, if all three of these men complete their respective don't-call-it-a-comebacks, will be that the cost of violating the public trust is modest, and the resulting embarrassment eminently surmountable. In fact, getting caught with your pants down (metaphorically or literally) might even garner you the kind of unique media attention not normally enjoyed by politicians, which translates into name recognition, which often translates into votes.

We're not in a position to evaluate the qualifications of candidates for public office in New York City. But in a larger sense, we think it would be a shame if voters in the Big Apple followed South Carolina in sending the world the message that American politics is really about celebrity, right after celebrity, famously, became about nothing.