In a highly intemperate open letter, UN High Commissioner for Human Rights chief Zeid Ra’ad Al Hussein (pictured) has attacked Geert Wilders, Nigel Farage, Donald Trump and a number of leaders of populist movements around the world as “demagogues and political fantasists.”

Not content with criticizing their politics, however, Hussein also compares the populist leaders with the Islamic State, asserting that “what Mr. Wilders shares in common with Mr. Trump, Mr. Orban, Mr. Zeman, Mr. Hofer, Mr. Fico, Madame Le Pen, Mr. Farage, he also shares with Da’esh.”

The letter is a transcription of a speech delivered by the High Commissioner at the Hague Monday, in which Hussein excoriates “populists” as purveyors of hate and enemies of human rights.

In his list of accusations, Hussein alleges that Mr. Wilders—leader of the Dutch Freedom Party—deals in “lies and half-truths, manipulations and peddling of fear,” creating a “factory of deceit, bigotry and ethnic nationalism,” before going on to tar all “populists” with the same brush.

“Populists use half-truths and oversimplification — the two scalpels of the arch propagandist, and here the internet and social media are a perfect rail for them, by reducing thought into the smallest packages: sound-bites; tweets,” Hussein writes.

“I am a Muslim,” Hussein writes. “And I am angry.”

What Hussein seems particularly “angry” about is the willingness of leaders of the populist movement to expose people to “the horrors of terrorism,” especially when “emphasizing it’s all the fault of a clear-cut group,” meaning Islamic terrorists.

“The formula is therefore simple: make people, already nervous, feel terrible, and then emphasize it’s all because of a group, lying within, foreign and menacing,” he wrote.

Although acknowledging that the actions of the Islamic State are “monstrous” and “sickening,” Hussein claims that they would be unsuccessful were it not for the instigation of the “populists.”

According to the commissioner, “in its mode of communication, its use of half-truths and oversimplification, the propaganda of Da’esh uses tactics similar to those of the populists. And both sides of this equation benefit from each other – indeed would not expand in influence without each others’ actions,” he alleges.

Hussein then goes on to accuse Mr. Wilders of “weaponizing” xenophobia and bigotry. “Communities will barricade themselves into fearful, hostile camps, with populists like them, and the extremists, as the commandants,” he warns.

Hussein ends his diatribe with an attempt to mobilize his “friends” against the populist movement.

“My friends, are we doing enough to counter this cross-border bonding of demagogues?” he asks. “Are we going to continue to stand by and watch this banalization of bigotry, until it reaches its logical conclusion?”

And in a direct challenge to the populist leaders themselves, Hussein declares that he and those like him will be the architects of the new century.

“We will not be bullied by you the bully, nor fooled by you the deceiver, not again, no more; because we, not you, will steer our collective fate.  And we, not you, will write and sculpt this coming century,” he said.

After reading through Mr. Hussein’s speech, one gets the distinct impression that the true “fear-monger” might very well be the one speaking, since he seems to attribute all the evils in the world—including Islamic terrorism—to the populist leaders.

So although he accuses his enemies of “demagoguery,” it is difficult not to wonder whether the label better applies to Mr. Hussein himself.

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