The Washington wise man Stephen Hess once said to me, “You know who’s going to get a second look? Bill Clinton.” This was in 1992, right after “60 Minutes” had revealed Clinton’s relationship with a woman whose name wasn’t Hillary.

I rolled my eyes. Guess who was right?

It is foolishness to pretend to know who is going to be the Democratic nominee in 2020. In 2003, a month before the Iowa caucuses, you would have been nuts to bet against former Vermont Gov. Howard Dean.

On Dec. 17 of that year, Dean led nationally with 23% of the vote . . . against then-Sen. John Kerry’s 4%. “Dean Pulls Away in Dem Race,” reported CBS News.

Then Kerry turned his fortunes around in Iowa, won the caucuses, Dean screamed a desperate “yeeeargh” in response and Kerry sailed into the nomination.

So what does this say about Joe Biden and his significant leads in national polling as well as in the polls in the first three critical states where Democratic voters will express their view on who their party’s nominee should be next year?

The lesson is that no one should go about crowning Biden — yet. Of course he can still lose the nomination. He could make a catastrophic gaffe that could either make him seem foolish, or thick, or wildly out of step, or just too old.

Any of these would immediately call into question his greatest strength: the idea that he is the Democratic candidate most likely to defeat President Trump.

He could have a senior moment where he forgets something or blanks on something — which could happen to any of us at any time, but that might be frightening coming from a 76-year-old man, a man who would turn 80 years old in the middle of his first term, should he become president.

Ditto with getting sick on the campaign trail; nothing his spokespeople could say would mitigate the sight of the body of the oldest person ever to run for president seeming not to be up for the job.

All that said, Biden couldn’t be in a better position for Biden. By which I mean, given the natural liabilities he has — age primarily and old white maleness when it comes to party activists secondarily — ­Biden has been making smart moves that have surprised many of those who secretly thought he was an over-the-hill boob.

He allowed everyone else serious in the field to get in the race and try to have their moment before he declared he would be running. In the first four months of the year, wags declared he would lose out on talented personnel and money and the like and seemed like maybe he didn’t have the fire in the belly.

Ha. The truth is there were too many candidates mostly chasing the same issues and the same activists and the same media coverage, and with the exception of Pete Buttigieg, none of them benefited from it.

Similar conventional wisdom has it that Biden suffered some from his flip-flop last week on the issue of federal funding for abortions. This is wrong, in my opinion, and almost comically so.

Conservatives suggested he’d fatally damaged his chances by joining extremists on this matter, since Americans by a 3-to-2 margin oppose such funding. Liberals suggested Biden had revealed himself not to be a strong enough supporter of abortion rights and that primary voters would punish him for it.

That isn’t the right way to look at this question. Biden found himself in a position where it was necessary for him either to change his position and support public funding or make a larger pronouncement about why he wouldn’t.

Quickly and decisively, he ripped off the Band-Aid and announced his support for federal funding.

Does he look unprincipled? Certainly from the perspective of conservatives and pro-lifers . . . who would never vote for him anyway. And what about the view of abortion supporters? Funny thing here. Biden’s decision to change his position is actually something they should welcome — because it is a tribute to the power they hold.

Pro-lifers loved George H.W. Bush when he flip-flopped, and just look at the behavior of evangelicals in relation to Trump on social issues. Making converts out of politicians is what activism is all about. Punishing someone for joining you is politically insane, even for people who often seem politically insane.

The truth is that Biden is running a nearly perfect campaign in the early going based on one implicit message: I can beat Trump, because I can speak to his voters and I’m not a crazy socialist like some of these other folks.

He might bollix that up; who can say? And when Democratic voters finally begin to make their choices, they may yet punish him for his supposed centrism. The only thing Joe Biden can do is be the best candidate it is possible for him to be, and so far, he’s doing that.

jpodhoretz@gmail.com