Pop Goes The News — Is Justin Bieber dealing with some private pain, going bonkers, or simply tiring of being one of the most famous people on the planet?

Whatever it is — and maybe it’s all of the above — it’s clear the 22-year-old Canadian pop star is going through something.

Since launching his Purpose tour earlier this year, Bieber has been publicly distancing himself from fans and, on social media, projecting an image of loneliness. His Instagram, which has nearly 68 million followers, is increasingly populated with solo “selfies” of the singer and views from hotel windows and the back seats of SUVs.

In a post earlier this month, Bieber told fans he’s “done” with posing for pictures with them when he’s out and about.

“It has gotten to the point that people won’t even say hi to me or recognize me as a human,” he complained. “I feel like a zoo animal, and I wanna be able to keep my sanity.”

When someone reacted by calling him a “prick” and reminding him that fans are responsible for his fame and fortune, Bieber fired back.

“If you think setting boundaries is being a douche I’m the biggest douche around but I think it’s smart and will be the only way I last,” he wrote. “I wanna enjoy life and not be a slave to the world and their demands of what they think I need to do!! I love the fact that I am able to make people happy but cmon if you truly were in my position you would understand how tiring it is.”

This last comment might explain Bieber’s palpable lack of passion on the Purpose tour, which is currently on a Canadian leg. (He performs Saturday in Quebec City, Monday in Montreal, and Wednesday and Thursday in Toronto.)

Bieber lip-synchs much of the show — even though the guy can sing — and largely sticks to a script when interacting with fans between songs.

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“Bieber seemed curiously detached from the action, although he was the centre of it,” Lynn Saxberg of the Ottawa Citizen noted in her review of Friday’s concert in Canada’s capital.

“In the early half of the show, his dancing was mechanical and his face expressionless, and he wasn’t too concerned if his voice hit every note because the backing track was always there.”

Critics in other cities have made similar observations.

At the Boston Globe, Maura Johnston said Bieber looked “sour at times” during his show in that city. (Then again, she erroneously referred to him as “a kid from the Toronto suburbs” — even though Bieber grew up 150 kilometres west of Toronto in the city of Stratford.)

Brett Milano of the Boston Herald opined that Bieber “seemed to be the only one in the sold-out house that wasn’t having any fun.”

He wrote: “At times he paced the stage looking distant while the dancers did their routines … There were also numerous moments in the production numbers where Bieber just plain stopped bothering to lip-sync, dropping the mic to his waist or holding it out to the audience, as the lead vocal carried on.”

Even on the second stop of the tour — which ends on Nov. 29 in England — there were signs that Bieber was bored.

According to Robert Collins of CTV Vancouver, “the feeling lingers that, despite what his script tells him to say, Justin Bieber has fallen out of love with his day job.”

Collins, who called the concert “strangely joyless,” noted Bieber seemed “disconnected and cold” and “smiles were infrequent.”

He added: “Worst of all, his few interactions with the crowd seemed forced: meaningless platitudes from an artist with a giant platform but nothing to say.

“Being Justin Bieber doesn’t look like fun at all.”

philly.com writer Hillary Rea said Bieber seemed “less than thrilled” to have to sing his early hits and she compared his “apathetic persona” to watching James Franco co-host the Oscars.

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At The Mercury News, Tony Hicks said at the San Jose concert Bieber “coasted, barely interested in doing more than what was required of him.”

He added that the pop star “had been mostly going through the motions.”

Jeff Niesel of the Cleveland Scene complained that Bieber “lip-synced his way through a concert that … ultimately lacked the kind of immediacy and intensity of a quality live performance.

“By the concert’s third song, it was apparent he wasn’t even trying to pretend to sing. He often held the microphone by his side during moments when his vocals could be heard in the mix.”

Niesel observed that during the Cleveland concert, “Bieber appeared detached and disinterested. Even his dance moves had a robotic quality to them.”

While the opinions of critics are rarely taken to heart by diehard fans — and Bieber has some of the most loyal fans anywhere — anyone who truly cares about the singer should take note.

Clearly, there is something going on with Bieber.

His history of bad behaviour and his recent life choices (he has added face ink to his collection of body art) can easily be dismissed as the folly of someone who grew up with fame and fortune surrounded by people living large off his success.

And, although no one has ever suggested Bieber is the smartest bulb in the box, his publicly-stated religious beliefs are seen by many as another sign of his being trapped in a fantasy world.

“On stage, no contemporary pop superstar appears to hate their own life as much as Bieber, who plunged to new sub-levels of poutiness,” Chris Richards of the Washington Post wrote about Bieber’s concert in D.C.

“He carried himself like a guy who has no friends.”

Calling the show “a joyless, lifeless, counterfeit act of contrition,” Richards said the singer was “wallowing through his choreography as if he was performing court-ordered community service.”

Richards opined that Bieber’s “physical detachment from the music was perversely mesmerizing, especially whenever he sulked across the stage at a pace unrelated to the tempo of the music, which was pretty much during the entire show.

“The signal was pure disdain.”

Richards suggested no one should bother “resenting the hyper-fame of a superstar who’s already doing such a fine job of resenting it himself.”

Jon Caramanica of The New York Times seemed to agree in his review of Bieber’s New York City stop.

“Maybe no one really hears him. If that’s the case, then the studied indifference that was the norm throughout this sometimes worrisome night … would be expected,” he wrote.

“Mr. Bieber gave the impression of a boy king who inherited subjects he didn’t ask for, responsibilities he’s not interested in shouldering.”

Caramanica, who called Bieber “joyless” and a “developmentally arrested child,” joked that while watching him perform, one might be tempted to call police to report a “suspected kidnapping in progress, subject forced into high-intensity labor.”

Of course, there are tabloid-style stories circulating that claim Bieber may be forced to cancel show on his Purpose tour due to “exhaustion.”

Don’t count on it. Bieber is collecting a massive payday from the tour.

After his second of two Toronto shows, Bieber will enjoy some time off until resuming his tour on June 11 in Winnipeg, followed by shows in Calgary, Edmonton and Saskatoon. He’s also got most of August off, except for a pair of concerts in Tokyo.

Writing in the Boston Globe, Ty Burr said Bieber’s concerts have devolved into “snit-fits in which the star steps out of his intricately choreographed traces and just stands there.”

But, Burr echoed the feelings that a lot of non-Beliebers have.

“It just makes me kind of sad, for a poor little (obscenely) rich boy who wants to be left alone in public and for a celebrity culture that locks emotionally unprepared children in prisons of fame and then jeers when they bang on the bars,” he explained.

“Bieber has spent the bulk of his career saying remarkably stupid things and looking deeply confused — I’m not convinced he’s all that bright — and that confusion has now seemingly tipped into misery.”

Burr added: “Imagine your every move scrutinized on every international inch of social media when you’re a young dude who only wishes he had the luxury of being an unexamined bonehead.

“Yeah, Justin Bieber wanted to be famous and he got his wish and he seems to hate it. It’s OK if you don’t care. It’s even OK if you feel compelled to let others know you don’t care on random Internet comment boards, just to prove you’re better than him.”

Burr offered the Canadian pop star some unsolicited advice. “Quit. If it makes you that miserable, finish your tour, honor your contractual obligations, and order your lawyers to get you out as quickly as possible.

“Disappear, grow a beard, write some conceptual cabaret songs that no one wants to hear. Get a real life. Find out who you are. Stop beliebing.”