By VIVIAN YEE

A children’s book author from Australia said she “loathed America” after her interrogation at Los Angeles International Airport. A retired police chief from North Carolina wrote that his customs screening made him “question if this is indeed home.”

And when Fadwa Alaoui, 39, a Moroccan-born Canadian, tried to drive into Vermont for her monthly shopping trip, she faced questions about her religious beliefs and politics and gave up her phone to be searched, only to be turned away.

“They treated us like criminals,” Ms. Alaoui said. “Like they have the right to do anything they want.”

As his administration wades past the 100-day mark, President Trump’s efforts to bar travelers from several majority-Muslim countries and to eject immigrants without legal status have heartened many supporters and inflamed widespread dissent. But for those not subject to ban or deportation, it is in the sterile screening rooms of the country’s airports and border crossings — where Americans and foreigners alike can be held, searched and interrogated for hours — that everyday people are most likely to meet the machinery of Mr. Trump’s government.

To judge by the chorus of travelers who have spoken out about a rough greeting at America’s doorstep, the customs experience is not helping Mr. Trump’s image.

But not all the blame for soured airport experiences can be directed this president’s way. Customs and Border Protection officers had the same discretion to screen travelers under the Obama administration, when Muslims and other travelers said they routinely endured intrusive and even discriminatory treatment. At this stage, the data available about customs officers’ activities does not support the charge that many more travelers are facing extra scrutiny.

Still, amid Mr. Trump’s attempts to harden American borders via wall, heightened vetting and a travel ban, the public is confronting a reality that went mostly unremarked in the past: In a country still struggling to define the balance between civil liberties and security nearly 16 years after the Sept. 11 terrorist attacks, customs officers wield broad authority over the millions of people who knock on the United States’ 328 gates each year.

In the limbo between leaving another country and arriving in this one, the officers have wide latitude to examine travelers, their baggage and their electronic devices while deciding whether to let them in. The rights that individuals, even citizens, are entitled to once inside the United States do not always apply while they are trying to enter it.

“You may think you are in the United States, but for legal purposes, you aren’t until that inspector admits you,” said Doris Meissner, a former commissioner of the government agency that evolved into the Department of Homeland Security after Sept. 11.

The administration has not issued new directives about screening arriving passengers, and current and former government officials argue that many people are predisposed to see the worst in officers now that they work for Mr. Trump.

“This is something that has always occurred,” said David Lapan, a Homeland Security spokesman. “The same things have happened under previous administrations.”

Civil liberties advocates and immigration lawyers, however, say they believe individual officers are fueling a disturbing escalation of enforcement, made plain in the aggressive tone as well as the frequency of travelers’ encounters with them.

“This is by no means an unprecedented thing,” said Hugh Handeyside, a staff attorney at the American Civil Liberties Union. “But it does seem at this point like the reports we’re hearing are not just isolated reports, but they appear to be part of a trend. Either the word’s gotten out unofficially or officially that this treatment can be tolerated.”

Customs inspections are routine: On a typical day in 2016, for instance, the agency denied admittance to 752 people at ports of entry and flagged 877 people deemed possible national security risks.

Still, for many travelers, officers’ ability to examine their phones — and even request their pass codes — has made even ordinary stops into alarming and uncomfortably personal encounters. Even after travelers enter the country, the customs agency can keep their phones for weeks while investigators forensically peer into their contents.

Electronic device searches were already on the rise under the Obama administration, with the number of travelers whose devices were searched more than doubling from 2015 to 2016. The monthly total of searches since Mr. Trump took office has remained roughly at the level that occurred during the last months of the Obama administration.

Ms. Alaoui, who drove to the border in early February, had intended to spend the day in Burlington shopping for toys for her 5-year-old son, who had just finished three months of chemotherapy.

On past trips, she said, she had spent about two minutes at the border before being waved through. This time, she and a cousin were questioned and held for four hours while their phones and car were searched.

After telling her to write down the pass code to her phone, a customs officer asked where she had been born (Morocco), how long she had lived in Canada (more than 20 years) and if she was a practicing Muslim (yes).

The interrogation quickly veered further toward religious questions, Ms. Alaoui said. The officer asked about her mosque and its imam. He pulled up videos found on her phone, videos of Muslim prayers and Arabic jokes that had circulated among her friends and relatives on social media, and asked her to explain.

Then he asked what she thought of Mr. Trump.

“I said he can do whatever he wants in his country. It’s not my business. I just want to cross the border to go shopping. Why are you asking me this question?” recalled Ms. Alaoui, who wears a hijab.

After they were photographed and fingerprinted, another officer told the women that they would not be allowed into the country because of the videos found on their phones.

Muslims have spoken for years of facing heavy scrutiny from customs officers, accusing the agency of racial profiling. So have people who may be mistaken for Muslims. Shah Rukh Khan, the Indian actor known as the “King of Bollywood,” who is Muslim, has made headlines for being detained three times in seven years while traveling to the United States.

The most prominent such incident in recent months occurred when Muhammad Ali Jr., the famed boxer’s son, was stopped by customs officers at Fort Lauderdale-Hollywood International Airport on Feb. 7. Mr. Ali, who had just arrived from a trip to Jamaica with his mother, said he had been led to a room where an officer asked how he had gotten his name and what his religion was.

In an interview, Mr. Ali said the officer had told him that he shared a name with another person who had been flagged for extra screening. He had never had trouble entering the country before, he said.

Officers have “an enormous amount of discretion” to question travelers, said Margo Schlanger, a law professor at the University of Michigan and a head of civil rights and civil liberties at the Homeland Security Department under President Barack Obama. While Customs and Border Protection has an anti-discrimination rule, she said, the agency has not put significant limits on officers’ ability to ask about religious beliefs.

In recent months, even non-Muslims have appeared to attract far more attention.

After flying back to San Francisco from Belgium, where he had been showing some of his artwork, Aaron Gach, an American artist, was stopped and asked repeatedly to unlock his cellphone for an officer to search, he said. Mr. Gach, 43, said he had been asked a series of questions about his work, his travel arrangements and the art show. He was released only after complying with the request to unlock his phone.

For noncitizens, formerly routine trips have turned fraught as travelers report encountering customs officers who question whether they are taking American jobs or being paid improperly.

“We used to hear about these things once in a blue moon, and it would be the talk of the office,” said Greg Siskind, an immigration lawyer in Tennessee. “Now people just basically roll their eyes because they’ve heard it so often.”

There was the Australian children’s book author, Mem Fox, who was nearly denied entry on her way to give a speech in Milwaukee after being questioned about the $8,000 honorarium — standard for such speaking engagements — that she had accepted from the organizers.

Ms. Fox, 71, who had traveled to the United States uneventfully more than 100 times in the past, characterized her questioning as “sadistic from the first moment,” though she was eventually allowed to continue on her way.

There was a 61-year-old ballet teacher from outside Toronto, Kennetha O’Heany, who tried to drive across the border in March to observe a children’s ballet class taught by another teacher in Ann Arbor, Mich.

Though she had made a similar trip in 2014, the explanation did not satisfy the officer, whom she said had told her, “If there are Americans that can do this job, then you are an illegal foreign worker.”

Her three-hour detention at the Windsor-Detroit crossing culminated in a pat-down search by two female officers, who were so thorough that they even felt between her toes, Ms. O’Heany said.

“I just kept thinking, ‘But I’m just a ballet teacher,’” she said.

And there was Erik Hoeksema, whose group of about a dozen volunteers from a church in Ontario was stopped and turned back at the Buffalo crossing in March. They had been on their way to the Jersey Shore to help rebuild houses destroyed during Hurricane Sandy in 2012.

No foreigners were allowed to do work for hire without visas, Mr. Hoeksema said he had been told. The fact that they were not going to be paid did not seem to make a difference.

“We don’t know if we were mistreated, or we just made a mistake, or who knows?” Mr. Hoeksema said, adding that he has heard of other volunteer groups being denied entry in the past. “I just wish that you could just come to common sense and look at our group and consider that there still is a need for Sandy relief.”

https://www.nytimes.com/2017/05/01/us/customs-airports-trump.html