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More than seven decades after his death, it seems impossible to escape the ghost of Adolf Hitler.

In Britain, a long-running dispute over a former Labour leader's alleged remarks linking Hitler and Zionism flared up again last week. During a war of words with European leaders last month, Turkish President Recep Tayyip Erdogan said politicians in the Netherlands and Germany were modern-day Nazis. And on Tuesday, Hitler featured prominently in White House press secretary Sean Spicer's astonishing gaffe (more on that below).

It's important that the horror of the Holocaust and the slaughters carried out by Hitler's war machine remain in the global consciousness. Hitler and the Nazis still, for many obvious reasons, provide the grim benchmark for the worst of what politics and humanity can become. But the temptation to invoke him to score a political point is one best left alone.

Indeed, the Trump White House and many of its cheerleaders in Europe's far right now profoundly resent the fascist analogies opponents sometimes throw their way. Faced with the toxic legacy of Western ultranationalism, they insist that their right-wing populist movements represent something altogether new, a turning of the epoch. But they can't so easily dispel the shadow of the past.

Which brings us back to President Trump's head spokesman. On Tuesday — the first day of the Jewish holiday of Passover — Spicer made an incredible unforced error when asked about the American response to Syrian President Bashar al-Assad's alleged use of chemical weapons. Spicer sought to further condemn Assad's actions by suggesting that even Hitler had not used them during World War II — ignoring, it seemed at the time, that millions of Jews and others were gassed in Nazi concentration camps.

"You know, you had someone as despicable as Hitler who didn’t even sink to using chemical weapons," Spicer said. "So you have to, if you are Russia, ask yourself: Is this a country and a regime that you want to align yourself with?"

White House press secretary Sean Spicer on April 11 said Adolf Hitler didn't use chemical weapons during World War II. Hitler's regime exterminated millions of Jews in gas chambers. (Reuters)

The point Spicer had hoped to make — underscoring new U.S. intelligence reports that Russia had sought to cover up Assad's recent chemical weapons strike — was lost on a bewildered press pack. Spicer was given a chance to clean up his mess, but his clarification raised more eyebrows.

My colleagues' transcript captures how baffling the moment was for everyone, Spicer included.

“I think when you come to sarin gas, there was no — he was not using the gas on his own people the same way that Assad is doing,” he said. "I mean, there was clearly, I understand your point, thank you. Thank you, I appreciate that. There was not in the, he brought them into the Holocaust center, I understand that. What I am saying in the way that Assad used them, where he went into towns, dropped them down to innocent, into the middle of towns, it was brought — so the use of it. And I appreciate the clarification there. That was not the intent."

This, of course, is not Spicer's first gaffe, but there are some shocking bits to pick out from the word salad above. First is the problematic inference that German Jews and others gassed by Hitler were not "his own people." Then there's the awkward labeling of death camps as "Holocaust centers" and the implication that those killed there were somehow not also "innocent." And, ultimately, there's the enduring question: At what point did any of this make sense as an appropriate metaphor?

The backlash was swift, and Twitter had a field day, summed up by this quick rewording of the gates of Auschwitz.

Spicer then came out with three different versions of an apology, promising that "in no way was I trying to lessen the horrendous nature of the Holocaust." He later continued his apology tour on CNN, but misspoke there as well, saying he didn't want to distract from Trump's Middle East plans and his agenda to "destabilize the region."

To be sure, this is all rather silly. But it's bizarrely not an isolated incident for the Trump White House, which has already made a hash of its messaging around the Holocaust and the prevalence of anti-Semitism at home and abroad. Trump's inner circle includes figures such as chief strategist Stephen K. Bannon, who has been accused of anti-Semitic speech in the past, and Sebastian Gorka, who won't renounce his links to an anti-Semitic, Nazi-affiliated organization in Hungary.

In Spicer's defense, his remarks were careless and misguided, not ideological. But the same can't be said of his president's kindred spirit across the pond.

Marine Le Pen, the far-right presidential candidate who is locked in a heated race in France,  controversially argued this week that her nation need not shoulder the guilt of the Holocaust any longer, referring to a specific episode in 1942 where thousands of Jews were rounded up and detained in Paris and later shipped off to their deaths.

“France has been mired in people’s minds for years. In reality, our children are taught that they have every reason to criticize her, to see only the darkest historical aspects," Le Pen said in remarks that drew rebuke from Israel's foreign ministry. “I want them to be proud to be French again.”

Critics say her National Front party is riddled with Holocaust deniers and neo-fascist sympathy for France's Nazi-collaborating Vichy regime. Her main opponent, independent centrist Emmanuel Macron, snapped back: "Madame Le Pen made a heavy political and historical mistake. This is the true face of the French extreme right, which I'm fighting." Le Pen, too, may see her fortunes doomed by Hitler's ghost.

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