Dear Bill de Blasio,

Everyone knows you’re a terrible mayor — maybe the worst in the past 100 years. But can’t you at least pretend that you love us? Like, by showing your face when we’re scared or in need of solace?

There’s a low-cost way to make people ignore your dereliction and laziness: Just act like every mayor before you when there’s a crisis.

A big part of the job is to be there for the city in moments of strain — both physically and symbolically. But you’ve been out to lunch — or out of town — since Day 1 of your rotten regime.

You stayed away for last week’s blackout to remain in Iowa for your ridiculous presidential campaign. You didn’t show up for the Puerto Rican Day Parade or veterans’ D-Day ceremonies. In May, you blew off a memorial event for victims of toxic exposure to Ground Zero — and blamed your staff. You skipped a murdered cop’s vigil in 2017 so as not to interrupt your junket to Germany.

You should learn from your City Hall predecessors. Some were great mayors, others lame. But they all knew the right public gestures to make when the chips were down, even though they might have needed to take a deep breath first.

Mega-billionaire Michael Bloomberg showed up at every stricken cop’s bedside. He rode to work on the No. 6 train. He read from the Koran at the funeral of a Muslim family killed in a 2007 Bronx fire. He spoke a brand of Spanish that amused some citizens but showed them that he cared.

Rudy Giuliani heroically led the city out of the 9/11 darkness at great personal risk. He never shrank from directly engaging the Big Apple’s people on the streets and sidewalks, even if that sometimes infuriated them.

Where you notoriously and repeatedly deplored a “tale of two cities,” David Dinkins found a “gorgeous mosaic.” After first seeming weak on rampant crime, he took to heart The Post’s front page admonition, DAVE, DO SOMETHING — making a speech to reassure the public and later by tapping no-nonsense Ray Kelly as top cop.

When a transit strike began, Ed Koch ebulliently led crowds into Manhattan over the Brooklyn Bridge to raise spirits in a troubled time. Koch knew it was important to show us he was in charge. You, Bill, duck your responsibilities, relinquishing increasing authority to Gov. Cuomo — and, during the blackout — your face-of-the-city ceremonial role to Council Speaker Corey Johnson.

Abe Beame cheerfully presided over the Tall Ships bicentennial celebration from an aircraft-carrier deck in the thick of the fiscal crisis he helped to create. Beame was an awful mayor, but at least he was honorable enough not to hide behind his commissioners and was willing to show his face in public. You skip mass transit for a chauffeured SUV. You shun the press except for self-worship in the cozy confines of weekly NY1 appearances.

Even elitist lefty John Lindsay had the common touch when it counted. Although he knew nothing about baseball, he got himself doused with champagne in the 1969 World Series-winning Mets locker room.

Bill de Blasio? You’re a Red Sox fan.

Bedside manner isn’t written into the City Charter. It isn’t the most fun part of the job, but it might be even more important than balancing the budget.

To put you more in touch with the Big Apple, I’d love to offer you a personal tour of the city.

I’ll show you the bright lights of Broadway, where you’re rarely seen at shows, and in restaurants you mostly shun except for a favorite old hangout in Park Slope.

Maybe you’ll meet some Times Square tourists from Iowa. They might be surprised to find you here — and so will we.