The man sleeping on a sidewalk mattress, next to his jar of urine and beneath a glimmering art installation of light created to brighten a city underpass, is not going away.

“We’ll come right back,” he vowed, after peeking out from under his blanket fort on a section of M Street. “I’ve been here my whole life, and I’m not going away.”

There are folks who believe that moving his mattress or his neighbors’ tents in the mushrooming encampment in the fast-gentrifying part of Washington now known as NoMa will get rid of them, will clean the city up. Spit spot.

Or that removing 23 benches in the park where he and his friends used to hang out during the day will make them disappear and make the park more enjoyable for everyone else.

Or that eliminating every bench in the stunning grand hall of Union Station, where travelers, locals waiting to meet someone and folks who don’t have a home used to sit, will make the city more welcoming, sparklier.

It’s hard to resist the urge to get rid of what makes us uncomfortable.

There are three homeless encampments parked beneath underpasses that put the city’s — and the nation’s — housing problem in plain view.

City trash trucks come and periodically dismantle the messy encampments, hauling away the treasures these folks have collected since the last cleanup.

Broken strollers, takeout containers, bottles, chairs, tents, a Christmas tree, an entire bookshelf, shopping carts, even an engraved coupe champagne glass stained with red liquid and perched on a chair this week are all part of the chaos that reminds everyone who passes what a calamity our war on homelessness is.

But cleaning up the mess doesn’t change the fact that there are American citizens, including veterans and people with minimum-wage jobs, who have no place to sleep.

The city has imposed a Jan. 16 deadline for the campers to vacate the K Street underpass in NoMa, arguing it has become an issue of pedestrian safety. People have to step into K Street, where the sidewalk is narrower and the tents take up more space, while walking past the encampments, city officials said.

It’s about law and order, see. And that’s why they have to go.

That’s the same reasoning the National Park Service gave to Street Sense reporters when they explained the removal of benches across from the New York Avenue Presbyterian Church on H Street in Northwest Washington.

There has never been a reason given for the gradual transformation of the Great Hall of Union Station, which had water fountains, benches and a two-story cafe when I moved here two decades ago.

The water fountains became planters, the cafe was removed after historic preservationists said it detracted from the character of the place, only to be replaced by electronic billboard advertising. And slowly, over the past few years, the benches have disappeared.

The National Capital Planning Commission met this week to discuss plans for the Union Station renovation and expansion.

One voice lamented the station’s history as a public space.

The “Great Hall has already largely ceased to be a place where people linger, and has instead become only a place they pass through, unless they are paying for an exclusive event,” Dan Malouff, an Arlington transportation planner and an adjunct professor at George Washington University who contributes to The Washington Post, said in comments submitted to the commission. (Among the private events taking over the space? Al Gore III’s wedding.)

But guess what? The homeless folks who used to linger there are still around. They haven’t been housed, fed and comforted. They just moved to another neighborhood that seeks to oust them, too.

The park doesn’t have benches anymore, but the guys who used to hang out there are still around.

If the tent cities are dismantled, the art-filled underpasses may offer “a moment of openness, a space to breathe, and a place where thoughts can drift away,” as the neighborhood’s news release promised, sure.

But the homeless people who lived there aren’t any better off. They still need a place to live.

Twitter: @petulad

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