Alice Hoagland clutched an American flag and screamed, “No Shariah in the USA.” She was joined by a few dozen other protesters in an anti-Shariah rally Saturday at Stevens Creek Boulevard and Winchester Avenue in Santa Clara — one of a number of rallies nationwide.

Hoagland’s calls were quickly drowned out by chants of “No justice, no fear, immigrants are welcome here,” from across the street at Stevens Creek and Santana Row in San Jose, where a “Unity rally” had been organized in protest of the anti-Shariah rally.

ACT for America, which organized the anti-Shariah rallies, is a nonprofit that bills itself as “the (National Rifle Association) of national security.” The group argues that Shariah, the Islamic law code, “is incompatible with Western democracy and the freedoms it affords.” The organization is designated as the nation’s largest grassroots anti-Muslim group by the Southern Poverty Law Center.

Hoagland, 67, said she doesn’t hate all Muslims, but that the flood of Islam into the U.S. is something to be feared.

“All I need to know about Islam, I learned on 9/11,” the Los Gatos resident said. “I lost my son on 9/11. How broad-minded am I expected to be?”

Hoagland’s son, Mark Bingham, was aboard United Airlines Flight 93 when it crashed into a field near Shanksville, Pa., after a group of passengers attempted to retake the plane from hijackers.

Hoagland said her son had plenty of Muslim friends and that she didn’t know if her son would approve of her presence at the anti-Shariah rally, but “I’m standing here.”

Standing nearby, Jack Smith, 20, waved a “Trump, Make America Great Again” sign. He was surrounded by people in red “Make America Great Again” hats and “Pro-Life” T-shirts.

The San Jose resident said he didn’t care if Muslims moved to the United States as long as they were properly vetted and would “conform to an American society.”

However, he had issues with the number of people he said were advocating for Shariah law, though he didn’t list any examples. And that wasn’t his only concern.

“Can you name one Christian country that’s throwing gays off rooftops?” he said. “Do you support women’s rights and gays rights?”

A Muslim man and several women in hijab came over with a box of store-bought cookies, offering it to the anti-Shariah protesters.

Most of the rally participants didn’t take them up on the offer.

They were met with signs that read, “Sharia (sic) Law Mutilates Little Girls” and “Women Are Bought and Sold As Slaves.”

Across the street, a large contingency from the Unity rally held signs that read “Everyone is created equal in the image of God” and “We all belong here. We will defend each other.”

They outnumbered the group of anti-Shariah law protesters and took up the entire sidewalk that led up to the entrance of Santana Row, a sprawling upscale shopping center in San Jose.

The Unity rally was organized by a Presbyterian minister and was co-sponsored by more than 100 other civil rights and interfaith groups including the Council on American-Islamic Relations, Meet a Muslim and Multifaith Voices for Peace and Justice.

The different groups kept to their sides, with a few stragglers from the anti-Shariah law side coming over and waving a “Sharia Law Opposes the Constitution” sign before hurrying back to their side. The rallies were both peaceful, police said.

Amani Hamed, a 28-year-old San Jose resident, stood amid the crowd at the Unity rally with her black hijab secured around her face. She was standing with other Muslims, who had come out with their children, and by people of other faiths and backgrounds.

What the anti-Shariah law protesters didn’t understand about Islam, she said, was that Muslims aren’t “allowed to govern other people by our religion” and that Muslims believe in the power of separation of church and state.

“We only govern ourselves,” Hamed said.

She came to the counter-rally not just to support Muslims, but also to stand in solidarity with anyone feeling targeted by President Trump’s administration and his supporters, Hamed said.

A report released by the council on relations in May found a 57 percent increase in anti-Muslim incidents in 2016 compared with 2015. In addition, the council reported that there was a 44 percent increase in anti-Muslim hate crimes during the same period.

“If we don’t stand together, we fall apart,” Hamed said.

The protesters were outnumbered in cities across the nation.

Hundreds marched through downtown Seattle, banging drums, cymbals and cowbells behind a large sign saying “Seattle stands with our Muslim neighbors.” Participants chanted “No hate, no fear, Muslims are welcome here” on their way to City Hall, while a phalanx of bicycle police officers separated them from an anti-Shariah rally numbering in the dozens.

In front of the Trump building in downtown Chicago, about 30 people demonstrated against Islamic law, shouting slogans and holding signs that read “Ban Sharia” and “Sharia abuses women.” About twice as many counterprotesters marshaled across the street.

A similar scene played out in a park near a New York courthouse, where counterprotesters sounded air-horns and banged pots and pans in an effort to silence an anti-Shariah rally.

“The theme of today is drowning out racism,” said counterprotester Tony Murphy.

The Associated Press contributed

to this report.

Sarah Ravani is a San Francisco Chronicle staff writer. Email: sravani@sfchronicle.com Twitter: @SarRavani