You can float like a butterfly and sting like a bee, but you can’t come in if your name is Ali.

That’s the way it was looking for Muhammad Ali Jr., son of the late boxing legend, when he returned home to the United States last month from a black-history event in Jamaica. Ali, who is American born and an American citizen, was detained for hours by Customs and Border Protection and interrogated about being a Muslim.

But if border officials have gained newfound zealotry under President Trump, they appear to have lost all sense of irony. Also last month, they detained Australian Mem Fox, who writes children’s books about — wait for it — tolerance and acceptance. She told the Guardian that she was treated with “shocking insolence” and “monstrous” and “horrible” behavior by people “gone mad.”

Henry Rousso knows about monstrous and horrible: He’s a leading French scholar on the Vichy regime and its collaboration with Nazi Germany. And Rousso, an Egyptian-born Jew, said he was detained for more than 10 hours after arriving in America last month to give a lecture. “The United States is no longer quite the United States,” Rousso wrote in the French Huffington Post.

A lot of Americans feel the same way.

Civil liberties groups report a broad increase in harassment by border officials. The ACLU says there has been a spike in hours-long detentions, interrogation about religion and the like. Though such practices predate the Trump administration, ACLU staff attorney Hugh Handeyside said border agents are “pushing the envelope” lately because “word has spread” that an aggressive posture is welcome.

This apparently isn’t related to Trump’s travel ban, which has been blocked in court, or any other explicit instructions. Rather, it appears that border officers, feeling emboldened by Trump, are taking it on themselves to act more aggressively.

And where would they get such an idea? Well, perhaps from the president’s tweet saying “I have instructed Homeland Security to check people coming into our country VERY CAREFULLY.” Or White House press secretary Sean Spicer’s claim that Trump wants to “take the shackles off” deportation officials.

A CBP spokeswoman told me that fewer people underwent secondary processing and phone searches last month than a year earlier, and fewer were “found inadmissible” — though she was unable to provide hard figures, so it was unclear whether this was a reflection of fewer people traveling. CBP processed 30.5 million travelers in February, down from 31 million a year earlier.

The claims of increased harassment of travelers are part of a larger concern that Trump, with his rhetoric, has a tendency to unleash some of his followers’ worst instincts.

Trump on Tuesday night responded admirably to the shooting of two Indians by a man who allegedly yelled at them to “get out of my country,” and to the threats and vandalism against Jews. “We are a country that stands united in condemning hate and evil,” Trump said. Amen.

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But hours before those fine words, Trump, meeting with state attorneys general, appeared to suggest that the threats and vandalism against Jewish targets might be false flags. White supremacists such as David Duke have been claiming for days that the acts were perpetrated by Jews.

Likewise, Trump reportedly rejected the advice of his new national security adviser, H.R. McMaster, who cautioned him that the term “radical Islamic terrorism” alienated Muslims. Trump used the line in his address to Congress, with exaggerated emphasis.

Certainly, Trump hasn’t authorized any sort of vigilantism against Jews or Muslims. But do would-be vigilantes perceive a wink and nod?

In the case of border officers, Abed Ayoub, legal director at the American-Arab Anti-Discrimination Committee, reports a noticeable increase in the aggressive treatment of arriving Muslims. “That could be related directly to the rhetoric,” he told me.

Anecdotally, at least, something has changed:

The detention of a former prime minister of Norway coming for the National Prayer Breakfast.

CBP requiring identification from all passengers arriving in New York on a domestic flight.

An undocumented woman seeking a protection order against her boyfriend arrested in the courthouse by immigration officials.

A NASA scientist, an American-born citizen, detained and directed to turn over his phone.

Canadians alleging they were turned away at the U.S. border after telling U.S. officials that they were coming to participate in anti-Trump protests.

A British Muslim schoolteacher traveling to New York with a group of children ordered off a plane on instructions from U.S. authorities.

And these are separate from what Trump has called the “military operation” to round up illegal immigrants, which has entangled “dreamers” supposedly protected under the Deferred Action for Childhood Arrivals program.

Normal? Mem Fox, detained on her 117th visit to America, didn’t think so. She wrote: “I kept thinking that if this were happening to me, a person who is white, articulate, educated and fluent in English, what on earth is happening to people who don’t have my power?”

You don’t want to know.

Twitter: @Milbank

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