These days, the 62-year-old Southern Californian finds herself shifting to English when she attends a baseball game or goes to a restaurant with her husband to prove that yes, she knows that language too, and to avoid the nasty looks she unfortunately gets while conversing in her native tongue.
"I notice more now with this current government that people are more impatient and there's more of a lack of understanding," said Mucarsel, of Anaheim, California. "When you speak Spanish, they automatically judge you thinking you don't speak English, and that is a huge ignorant idea."
Being multilingual in the United States brings advantages like job opportunities and social connections. But speaking something other than English in some public places also can risk drawing unwanted attention, as evidenced recently by widely viewed videos of a rant by a New York lawyer against restaurant workers and a Border Patrol agent in Montana questioning people for speaking Spanish.
In that May 16 encounter, the agent told Ana Suda and her friend he wanted to see their IDs because he overheard them conversing in Spanish in a store, and he deemed that suspiciously rare in her hometown of Havre, about 30 miles (48 kilometers) from the Canadian border. A U.S. Customs and Border Protection spokesman said the episode is under review, but noted that agents have broad discretion to question people.
Afterward, Suda steered clear of blaming President Donald Trump, at least not directly, for what she and others perceive as rougher treatment from strangers.
"What I know is like, probably a year ago, a year-and-a-half ago, I started feeling more, you know, like that people say a little more things," she said.
It's not just Spanish; native speakers of Arabic, Farsi and many Asian and Indian tongues have long had to make the personal choice of when to stray from English. But some Latinos in particular feel the Trump administration's harsh rhetoric and tougher policies toward immigrants from Mexico and Central America have helped turn unwelcome glances into open hostility.
"The bottom line is anti-immigrant sentiment is now a part of mainstream discourse. It is not only present in barrooms, in the heartland - it is present at press briefings in Washington, D.C.," said Brian Levin, director of the Center for the Study of Hate and Extremism at California State University, San Bernardino.
In the United States, one in five people age 5 and over speak a language other than English at home, according to data from the U.S. Census Bureau. In immigrant-friendly Los Angeles, more than half of people do.
About 60 percent of people in the country who speak another language said they also speak English very well.
For most, that language is Spanish. About 40 million people in the United States speak Spanish and surveys have shown that retaining the language is important to Latinos, said Jens Manuel Krogstad, a writer at the nonpartisan Pew Research Center in Washington.
For many, speaking Spanish isn't an option but a necessity to communicate with immigrant parents, grandparents or friends who don't know English - or know enough to get by but feel more comfortable in their own language.
For others, it is a choice - sometimes deliberate, and sometimes the barely conscious tug of a language they've always known. It's the language of their first words. Or the language they were taught math in, which makes the task of counting change easier even though their English is flawless.
Or maybe they fell in love in Spanish, and it just doesn't translate.
Some native speakers might slip into Spanish to evaluate an iffy deal they're being offered on a car, or to gently reprimand misbehaving children without the rest of the world knowing.
"When I was growing up my mom spoke to us in Spanish when we were in trouble," said Vanessa Viana, 37, who grew up in Northern California. "I think she was raised that things we say in Spanish are private."
Viana said that doesn't really work where she now lives in Los Angeles since Spanish is so prevalent. She speaks Spanish everywhere with her two young sons, hoping they'll retain the language and take pride in it.
The New York lawyer's tirade also drew winces from official English advocate Mauro E. Mujica, a Chilean immigrant who speaks five languages including Spanish. The chairman and chief executive of U.S. English said he wants the country to encourage immigrants to learn English - not preclude them from speaking other languages.
"I think that is a crazy overreaction that gives a bad name to people like us who are trying to have the ability to make English as an official language," Mujica said. "People can speak whatever they want to speak when they're in public or with their friends."
In recent years, schools in states around the U.S., not just the immigrant-heavy coasts, have honored students who graduate high school knowing English and at least one more language. In careers ranging from law enforcement to health care, people said being bilingual has been an advantage and brought more opportunities.
Diana Olivera said knowing Spanish has proven critical at her job as a pediatric nurse at a Phoenix hospital, where most of her patients' families speak Spanish.
"The people that I work with, they love it because it's beneficial to all of us," she said.
Above all, Spanish, for many, is the language of family and culture, and pulls on the heart. Mucarsel, who speaks fluent English with an accent that she said has drawn discrimination, speaks Spanish whenever she feels comfortable doing so or when she wants to help others feel at ease. And it's the language she naturally turns to when she sees her family.
"It is lovely to speak your native language," she said. "It comes from your soul."
Taxin reported from Orange County, California. Associated Press correspondent Matt Volz in Helena, Montana, contributed to this report. Follow their work on Twitter at https://twitter.com/ataxin , https://twitter.com/astridgalvan and https://twitter.com/mattvolz .
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