I’d like to personally bop over the head the next Democrat who says that Michael Bloomberg shouldn’t be running for president because he’s a billionaire. Let’s give thanks that a simple-minded dismissal of rich candidates didn’t sink FDR’s chances.

Billionaires are not the enemy. If you believe that those raking in astronomical incomes should be paying higher taxes — and Warren Buffet and I do — that is a job for our elected representatives who write the tax code.

Bernie Sanders is currently rattling his tongue about striking fear in the hearts of the “billionaire class.” (It was millionaires until he became one.) The news that Bloomberg may vie for the Democratic nomination has displeased him. “You ain’t gonna buy this election,” he thundered.

Lost in the tussle over Elizabeth Warren’s proposed wealth tax are assertions by several billionaire critics that, actually, they wouldn’t mind paying higher taxes. They don’t like how her proposal is being portrayed as a kind of punitive measure to control bad people, rather than a means to raise revenues.

Also, a wealth tax is a crazy way of funding government. Warren would levy a 2 percent tax on assets above $50 million. Who is going to place a value on art collections, yachts and jewelry?

The sensible way to raise this group’s taxes is the traditional way: Increase marginal rates applied to the top incomes.

Sweden tried and then gave up on a wealth tax. Sanders should know that his beloved social model of Sweden has more billionaires per capita than the United States. Their billionaires pay plenty of tax on their incomes.

It’s wise to judge a rich candidate by what that person has done other than accumulate wealth, how the money was made and whether the skills involved are applicable to holding office. Some fortunes require not a day of work. Ask the seven Walmart heirs on the Forbes 400 list of richest Americans.

After making his first billions, Bloomberg labored in the urban trenches as a successful mayor of New York City. He started shortly after the Sept. 11 attacks, when people were afraid to come into town and businesses were reeling.

The city’s revenues plummeted, so he raised real estate taxes to maintain essential services. This was also no time to lay off public workers, who had performed so valiantly throughout the crisis.

Conservatives went straight for Bloomberg’s throat. His “tax-and-spend liberalism will cost a fragile New York many thousands of jobs and make its recovery uncertain,” the right-leaning City Journal opined. The opposite happened.

Bloomberg checks most of the progressive boxes. He’s been a tiger in the fight against global warming. He backs gun control and reproductive rights. And he has long credited immigration with “keeping New York City and America at the front of the pack.” Despite some controversial policies, he won election three times in one of the planet’s most racially and ethnically diverse cities.

It would be amusing to see President Donald Trump try his tycoon swagger on a debate stage with Bloomberg. Bloomberg built a great media empire from nothing. Trump parlayed a $413 million inheritance (in today’s dollars) from his father into six bankruptcies.