When Donald Trump, Ben Carson and other political outsiders first denounced political correctness, they instantly struck a nerve. They were promising to peel back the mushy language that government and so-called sophisticates use to conceal simple truths.

I was hardly alone in liking the vow of honesty, and as Trump and Carson rose in the early polls, their rivals, the media and voters got into the act. Denouncing political correctness quickly became routine and is now the leading ­cliché of the campaign.

Alas, that makes it part of the problem it was meant to solve.

Look at it this way: Accusing someone of being politically correct is the politically correct way of saying they are lying. Let’s cut to the chase and just say it, for God’s sake!

That urge came over me as I watched Sens. Marco Rubio and Ted Cruz, along with Jeb Bush, ­argue over each other’s immigration flip-flops during last week’s GOP debate. Because Fox moderators used videos to demonstrate the differences between where the candidates once stood and where they stand, the truth was obvious, yet none of the three ­rivals dared say it.

Why couldn’t even one acknowledge that he changed his position and explain why? And if none would, why didn’t the others just say, “You’re lying”?

These are three men I admire, yet each lacked the courage to be honest on a crucial point during a televised job interview. When did the truth become so toxic and ­untruths so acceptable?

Spin and puffery have a long history in politics, but something has snapped in our culture that we no longer even expect our leaders to talk straight. We have become immune to lies and the ­liars who tell them.

I blame it on the Clintons. Their survival despite a quarter-century of shameful dishonesty has led the way in lowering the bar for ­integrity in public life.

One result is the disgust that most Americans have for government. Another is that many voters are willing to overlook other deficiencies in anyone they believe is honest, such as Trump and Bernie Sanders. Americans desperate for the truth will sacrifice traditional litmus tests to get it.

We would have better politics and be a better country if we had stopped the Clintons years ago. It was obvious before his election that Bill Clinton was a stranger to truth, and it soon became obvious that Hillary was no better. Recall the sensation in 1996 when the late William Safire used his New York Times column to speak in shockingly plain terms about ­Hillary.

“Americans of all political persuasions are coming to the sad ­realization that our First Lady — a woman of undoubted talents who was a role model for many in her generation — is a congenital liar,” he began, 20 years ago this month.

“Drip by drip, like Whitewater torture, the case is being made that she is compelled to mislead, and to ensnare her subordinates and friends in a web of deceit.”

Safire took a lot of heat, with critics disputing not so much his conclusion about a raft of incidents but the bare-knuckled way he expressed it. Bill Clinton’s press secretary supplied obligatory chivalry by saying, “The president, if he were not the president, would have delivered a more forceful response on the bridge of Mr. Safire’s nose.”

Safire used a later column to defend his language with a dissection of both “congenital” and “liar.” He cited Winston Churchill, who had once chided a colleague for “terminological inexactitude,” before quoting Churchill’s advice that “short words are best, and the old words when short are best of all.”

And so they are, yet our pretensions keep getting in the way. A downside of the upscaling of modern life is a fondness for false sensitivity and verbal cotton candy.

[The Clintons’] survival despite a quarter-century of shameful dishonesty has led the way in lowering the bar for ­integrity in public life.

Nobody “watches” anything anymore, they “monitor” it. No action is taken until all “stakeholders” are consulted. We say “price point” when we mean “price.” And is there no other way to express sympathy besides pledging “thoughts and prayers”?

This lament is not about semantics. It is about the urgent need for plain honesty in American life. Being politically correct is not being kind. It is being dishonest and we are reaping the consequences.

Consider that the passage of time has confirmed Safire’s conclusion about Hillary Clinton. She was a liar then, and remains one today.

In a world that prized truth, she couldn’t be dog-catcher. In our world, she could be president.

Blas’ real progressivism

Reader James Giorgio had a “Eureka!” moment about Mayor Putz.

“They say Bill de Blasio is a ‘progressive,’ ” he writes. “I finally know what that means. New York City has become ‘progressively’ worse since he took office.”

Bloomy’s ‘Sharp’ turn

Mighty curious that one of Michael Bloomberg’s first steps in a possible White House run was to dispatch an aide to meet with Al Sharpton. The Rev. responded with many nice words about the former mayor, which suggests an endorsement is possible.

In return, maybe Bloomy can write a fat check to pay off Sharpton’s tax debts. That way, taxpayers would get something, too.

City Hall horsing around

Attention, New Yorkers. City Hall thinks you are dumb. Really, really dumb.

In what seemed a case of sloppy timing, the City Council scheduled final votes on two major issues for the same day. But the timing now looks intentional, and suspicions are growing that the items are linked in a quid pro quo.

One item is the deal Mayor Bill de Blasio made to move the carriage horses to a renovated building in Central Park, at a cost of about $25 million. The move is publicly unpopular, and council approval was seen as iffy.

But the bill is moving quickly, along with the second one, which would give top officials whopping raises. Council members, who now make $112,500, plus committee bonuses, would get an increase to $148,500, a jump of $36,000 or 32 percent.

That’s nearly $11,000 more than the level recommended by a mayoral commission, which suggested that members get $138,315, an increase of 23 percent. In both cases, bonuses would be eliminated and there would be limits on outside income.

With the bills now expected to pass this Friday, there is wide belief that the Mayor’s Office agreed to the higher raises for council members in exchange for their supporting his carriage deal.

A curious fact is that other officials in line for raises, including the mayor, are getting only the initially recommended amounts. The council alone is getting a double boost.

If there is a link, it will mean the horse deal began with what looks like a payoff to big de Blasio contributors and will end with a payoff to the council. There isn’t enough perfume in New York to hide the foul odor, and that is no insult to the horses.