OPINION — There is no need to speculate about President Donald Trump’s strategy for reelection. He plans to — and needs to — destroy his general election opponent.

That’s the only way an incumbent president with a job approval rating in the low 40s and sitting at 40 percent in hypothetical ballot tests can possibly win.

Trump loves the combat and the name-calling. It wouldn’t matter if the Democrats nominated Mother Teresa (were she still alive). Trump would mock her, give her a demeaning nickname, portray her as selfish and self-centered, and brand her a phony. That’s what Trump does.

But don’t take my word for it. It was his wife, Melania Trump, who told a crowd in Milwaukee, Wisconsin, in April 2016, “As you may know by now, when you attack him, he will punch back 10 times harder. No matter who you are, a man or a woman, he treats everyone equal.”

“Equal,” as in equally nasty.

Politics can be a rough game. I get it. I’ve been covering campaigns for the last 40 years. No, politics ain’t beanbag. 

But in the old days, political dirt was shoveled under cover of darkness, circulated by whispering campaigns or anonymous handouts left on car windshields on Sunday mornings.

Trump has taken negativity to a new level.

He delivers the attacks himself, often during rallies or press events. So whether the Democrats nominate Joe Biden, Elizabeth Warren, Pete Buttigieg, Cory Booker, Bernie Sanders, Amy Klobuchar, Steve Bullock, John Delaney or someone else, you can be sure that Trump and his allies will run the same slash-and-burn campaign they did in 2016.

Something on everyone

There are no flawless candidates this year or any year. Democrats shouldn’t be looking for one.

Obviously, some Democrats are carrying more baggage than others.

Sanders’ embrace of socialism, for example, may earn him points for being frank, but it’s a considerable liability in a general election.

Biden’s son Hunter’s membership on the board of a Ukrainian energy company is also a liability for his father, though not one so serious that it would define the former vice president’s candidacy.

We don’t now know what opposition research Trump has on each of the Democratic candidates, but Democrats would be wise to assume he has something on everyone — and if he doesn’t, he’ll just make something up, as he has done in the past.

He is, after all, trying to muddy the waters so that he wins a chunk of voters who don’t like him but dislike his opponent even more.

Remember, Trump won the 2016 election even though he had worse ratings that Hillary Clinton, according to that year’s exit poll. 

Forty-three percent of voters had a favorable opinion of Clinton, compared to 55 percent who saw her unfavorably. Trump’s rating was measurably worse at 38 percent favorable and 60 percent unfavorable.

A solid 55 percent of respondents said Clinton had the right temperament to be president, while only 35 percent said the same of Trump. And while 52 percent of those polled said Clinton was “qualified to serve as president,” only 38 percent said Trump was qualified.

Clinton even bested Trump, albeit very narrowly, when it came to honesty and trustworthiness. Only one in three respondents said Trump was “honest and trustworthy,” while 36 percent said that that description applied to Clinton, who was carrying years of political baggage.

Given all of those numbers, Clinton should have won the election comfortably. But she didn’t, in part because many voters didn’t trust her, eight years of Barack Obama produced an anti-Democratic fatigue, and a slice of voters were so frustrated with unfulfilled promises that they took a flier on an outsider they hoped could change the trajectory of the country in a positive way.

Even if many voters had doubts about Trump — even if it was a gamble to vote for someone unqualified and with the wrong temperament — wasn’t it worth the risk, given the alternative?

Four years later

Trump’s problem is that the rhetorical question he asked of black voters in 2016 — “What do you have to lose?” — now has a different answer for many voters (regardless of race) than it did four years ago. 

He will continue to run against the establishment, the Deep State, the national media, Obama, Clinton and his eventual Democratic opponent. But unlike 2016, when voters could vote for Trump in the hope that he would become “more presidential” and would “grow” into the office, those voters now see that the exact opposite has occurred.

And while millions of Americans who still support the president may like his political incorrectness and the chaos he produces on a daily basis, some of those 2016 supporters won’t want to stomach another four years of disarray and insanity. It is simply too fatiguing.

So the president has no option but to drive his opponent’s negatives higher. That means attacks on his or her character, judgment, health, integrity, intellect, family members, friends, business associates and personal behavior.

And yes, Trump will brand him or her a socialist who wants open borders and gun confiscation, and who supports closing all houses of worship, destroying the U.S. military, bankrupting the country and letting rapists and murderers run free.

And he’ll probably do all that before the end of September. Just imagine what the last month before Election Day will be like.