In Soviet times, it was common for government critics to be branded as "traitors" and "enemies of the people." That sort of rhetoric largely faded away after the Soviet Union fell a quarter-century ago.

But now, it's returned — and much of it is coming from Ramzan Kadyrov, the leader of the Russian republic of Chechnya.

Kadyrov likes to portray himself as an action hero from the rugged Caucasus Mountains of southern Russia.

The 39-year-old leader appears to have nearly unlimited power in the predominantly Muslim Russian republic, which historically has had troubled relations with Moscow, including two wars in the post-Soviet period. But Kadyrov has aligned himself closely with Russian President Vladimir Putin.

In a pro-government rally last week in Grozny, the Chechen capital, tens of thousands of people turned out, though some told reporters that they'd been ordered to attend.

Kadyrov wasn't there, but one of his closest political allies, Adam Delimkhanov, whipped up the crowd with shouts of "Allahu akbar" (God is great) and a denunciation of Putin's opposition.

"We know our enemies and the traitors of this country," Delimkhanov said. "We have the lists of them in our pockets. Wherever they are, they will answer according to the law... and not by the law." The implication being that they will be dealt with outside legal channels.

Delimkhanov didn't name names, but people in the crowd were provided with posters that included caricatures of some prominent Russian human rights campaigners, including 88-year-old Lyudmila Alexeyeva, the head of the Moscow Helsinki Group. Alexeyeva has been a staunch critic of the Kremlin's crackdown on opposition activists and civic groups.

Kadyrov had even stronger words against so-called traitors to Russia in a recent interview.

"They are the enemies of our state," he told state-controlled Grozy TV. "And wherever they appear, any patriot ought to smash their faces, because they're not citizens of Russia, they're the enemies of our people."

A recent Instagram post by one of Kadyrov's allies shows the Chechen leader holding his snarling dog, named Tarzan, on a leash. Chechen parliament speaker Magomed Daudov, who posted the picture, said Tarzan's fangs itch whenever he sees people from the opposition. Daudov didn't specify who he was talking about, but the list of opposition "enemies" typically includes politicians, independent journalists and human rights activists.

Kadyrov began his career as a rebel, fighting against the Russians under the lead of his father, Akhmad Kadyrov, a Muslim cleric and Chechen separatist leader.

The Kadyrovs switched allegiance to the Russian side during the second Chechen War (1999-2000), in part because the father, Akhmad Kadyrov, feared that the insurgents were dominated by Islamist radicals. Ramzan Kadyrov was appointed president of the republic by President Putin in 2007, a few years after his father was assassinated in a bomb blast.

Since then, Kadyrov or people associated with him have been accused in a series of murders of journalists and opposition figures, charges he has always denied.

Kadyrov portrays himself as a loyal foot soldier of Putin. Earlier this week, after he made his threats against the opposition, the Russian president praised the Chechen leader for his "effective work."

Top Russian politicians have had little to say about Kadyrov's behavior, suggesting that he either enjoys Kremlin approval or that people are afraid to oppose him.

But Tanya Lokshina, the head of Human Rights Watch in Russia, says Kadyrov's recent actions to crack down on and humiliate his opponents may signal that his position has become less stable.

"This is not a sign of strength, but rather a sign of weakness," she says. "If Mr. Kadyrov is being so aggressive, if he's being so active in trying to demonize his critics, it means that he's worried."

Lokshina thinks that Kadyrov is feeling vulnerable in his relations with the Kremlin, and among his own people in Chechnya. She points out that just over a year ago, Islamist militants staged one of their most violent attacks in Grozny, killing more than a dozen policemen, "and Moscow understood that Kadyrov was not as in control as he claims to be."

Lokshina also notes that Kadyrov has been cracking down on dissent at home, sometimes forcing local critics to appear on television to be berated and humiliated.

"There was a very prominent case recently," she says, "when a young man who said critical things about Mr. Kadyrov on his account on social networks was found by Kadyrov's security agencies, and they actually forced him to take his pants off, which is above and beyond for Chechen men. You're talking about public humiliation, there's nothing worse than that."

Lokshina says the man was forced to stand on a treadmill, on television, without his pants, and apologize to the leader.

She says the public humiliation has begun to create its own kind of backlash. Some people in Chechnya see it as a kind of collective punishment that offends their honor.

Some opposition figures have produced mocking " apologies" of their own, in which they claim to be sorry for whatever offense they may have caused the Chechen leader.

Kadyrov has also become the object of a satirical song, " Ramzanka Dyrov, Your Hero," in which the Russian word for hero is made to rhyme with the word for hemorrhoid.

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