To understand the madness gripping American leftists, try to see the world through their eyes. Presto, you’re now part of the raging resistance.

Like the Palestinians who mark Israel’s birth as their nakba, or tragedy, you regard Donald Trump’s 2016 victory as a catastrophe. It’s the last thing you think of most nights, and the first thing most mornings.

You can’t shake it or escape it. Whatever you watch, listen to or read, there are reminders — Donald Trump really is president.

You actually believe the New York Times is too nice to him, so you understand why a Manhattan woman urged a reporter there to stop covering Trump to protest his presidency.

And where the hell is Robert Mueller? He was supposed to save us from this nightmare — that’s what Chuck Schumer banked on. Well?

You spend your tax cut even as you rail against the man who made it happen. And you are pleased that cousin Jimmy finally got a job, though you repeat the daily devotional that Barack Obama deserves credit for the roaring economy.

And now this — Justice Anthony Kennedy is retiring, and Trump gets another Supreme Court pick. The court might tilt right for the rest of your life. He’s winning.

NOOOOOOOOO!!!

In a nutshell, our visit to the tortured mind of a Trump hater explains everything from Saturday’s mass marches to why a Virginia restaurant owner declared No Soup for Sarah Huckabee Sanders.

Their loathing for Trump is bone-deep and all-consuming. This is war and they take no prisoners.

For most marchers, border policies offer a chance to vent. They didn’t make a peep when Obama did the same thing.

If children are their main concern, they could help the 23,000 New York City kids living in shelters. Or they could have attended the funeral of Lesandro Guzman-Feliz, the innocent Bronx teen hacked to death by a Dominican gang.

Instead, they give in to Trump Derangement Syndrome, which causes them to immediately and absolutely adopt the opposite position of the president’s — facts and common sense be damned.

Alas, they may look back on the last few months as the good old days. For Trump, despite his stumbles and the Mueller shadow, is finding a political sweet spot.

He is reaching a high-water mark in his presidency, with his support growing and expanding. Events, including big Supreme Court rulings and Kennedy’s retirement, give him chances to pad his advantage.

It’s a swift reversal from just 11 days ago, when Trump was sucking wind. The media was — again — treating him like a piñata over the separation of families on the border, and the White House was ready to fight a war it couldn’t win.

Then the president suddenly called off the dogs to sign an executive order ending family separations. Much of the hot air instantly came out of the resistance balloon, though protests continue because the left is embracing little or no border control as its passion of the moment.

Whether it’s because of Trump’s quick reversal and/or the left’s overreaction, polls are capturing the president’s rising fortunes. One survey showed most Americans were not nearly as sympathetic to the illegal border crossers as the media.

“I think it’s terrible about the kids getting split up from their parents. But the parents shouldn’t have been here,” a Minnesota woman told the Times.

Another poll shows Trump with 90 percent support among Republicans, matching the backing of President George W. Bush after 9/11.

And his support is broadening. A Harvard CAPS/Harris poll showed his approval rating hitting 47 percent, a two-point gain in one month driven by a 10-point swing among Hispanic voters and a four-point gain among Democrats.

Pollsters attributed the rise to the strong economy and that a whopping 75 percent approved of the president’s decision to meet with North Korean dictator Kim Jong Un.

Finally, a Pew finding about Trump supporters upends stereotypes: Just 31 percent are white men without college degrees, while 66 percent are college graduates, women or nonwhites.

These signs of the Big Mo switching sides came before two Supreme Court rulings that favored Trump. The first upheld his revised travel ban for a handful of Muslim-majority nations, saying it was within his ­executive authority.

It rebuked lower-court judges who bought the partisan canard that it was a “Muslim ban.” Their invalid rulings stood in stark contrast to plain readings of the law and show them to be hacks blowing with the political wind.

The second ruling, which blocks municipal unions from forcing workers to pay dues, is a tax cut for workers who opt out and a blow to Dems in New York, New Jersey and other blue states. The nexus between unions and Democrats turned those states into one-party fiefdoms — and resulted in union contracts taxpayers can’t afford.

Both rulings were 5-4, with Kennedy supplying the swing votes in an otherwise evenly divided court. That Trump will soon nominate his successor and likely have that person confirmed before the midterm elections improves GOP chances to hold Congress and the president’s chance to cement his legacy as an agent of dramatic change.

Because Democrats set the agenda for most media, the immediate talking point was that abortion rights are threatened with another GOP pick. While that is unlikely, given the Supremes’ traditional respect for precedent, the larger fact is that there is much more at stake than any single issue.

Consider that the travel-ban case upheld broad presidential authority on national security, and the union ruling was among several supporting First Amendment rights of individuals against government infringement.

Rulings like these have long-term cultural and political impacts and explain why Supreme Court appointments can have an outsize influence on a president’s legacy.

Already Neil Gorsuch, Trump’s first pick, is enormously popular with those who believe a justice’s job is to make sure laws pass constitutional muster, not legislate from the bench. A second pick in the Gorsuch mold would secure a majority on the court for curbing government’s appetite for more domestic power, perhaps for decades.

And that could do something extraordinary for Trump’s legacy. All else being stable, putting the Supreme Court on an enduring constitutional footing would make his presidency one of the most consequential of any age.

Cue the wailing.

New Deb mini-me

New Schools Chancellor Richard Carranza is a great fit with Mayor Bill de Blasio. Like his boss, Carranza is obsessed with counting racial beans and believes the answer to every problem is more money.

One of them was more than enough. Two may be more than even New York City can handle.

An easy ‘pass’

A friend writes with a question: “How is it that if you arrive at JFK Airport without a passport, you are sent back to your place of origin, whereas if you cross the Rio Grande River without a passport, you are not sent back?”