(RNS) Under a cloud of suspicion and distrust after the 9/11 attacks, there were stories of men named Muhammad who started going by "Mo," mosque leaders telling their flocks to lie low and women leaving their headscarves at home.

And then there was Asma Mangrio.

"My husband was nervous with me driving alone with my scarf on after 9/11," said the 37-year-old mother of three. "But I said I'm not taking it off. I'm not going to let something like this stop me."

Instead, Mangrio organized an information session for neighbors in her apartment complex, explaining her beliefs and condemning terrorism.

She threw herself into life at her San Francisco Bay Area mosque, and in 2005 helped launch Muslim Unity Day, which draws as many as 4,000 Muslims to a local amusement park.

"Everywhere you go in that park, you see Muslims. It took me until the second year to realize that this is the first time in my life that I have been a majority in a public place in America," she said.

While many Muslim Americans sought invisibility after 9/11, others did the opposite: growing beards, donning headscarves and skull caps, and making sure people knew they were Muslim.

The point? To be visible, and to challenge the notion that Muslims are oppressed, uneducated, dangerous or extremist.

"There's nothing wrong with being an outwardly devout Muslim, and a proud loyal American," said Hassan Shibly, who was in 7th grade on 9/11.

As a teenager, he was taunted by classmates who called him "Osama" or "terrorist."

But when Shibly began his studies at the State University of New York at Buffalo, he grew out his beard and started wearing a kufi, or skullcap. Sometimes he wore a jubah, a traditional Arabic gown, when he chaired meetings of the student senate.

"People got to know me and like me in regular clothes, and then they'd see me in something they wouldn't expect, and that would really help break down the stereotypes," said Shibly.

He went on to law school and worked for judges over summer break. And while he opted for suits instead of the jubah, he wouldn't let go of the beard or kufi. People were "astonished," he said, to see him "chilling with the judge."

Last spring, Shibly turned a few more heads when he got an airport job -- with full security clearance -- handling luggage on the tarmac.

"It hopefully broke some stereotypes because you've got this guy with a beard and kufi, looking like what they're probably afraid of, loading and unloading their planes," said Shibly, who now directs the local branch of the Council on American-Islamic Relations in Tampa, Fla.

The Muslim-and-proud message, however, isn't just directed at critics, or those who think they know everything they need to know about Islam. It's also directed within.

"We need to teach our Muslim youth what the reality of the religion is, and to help them feel a sense of pride in their religious, cultural and ethnic heritage, and also to teach them and Americans that this is part and parcel of the American ideal," said Sheikh Yasir Kazi, a prominent cleric who teaches Islamic courses at Rhodes College in Memphis, Tenn. 

Other Muslims have adopted a uniquely American method of sending a message: plastering it on a T-shirt.

At Hijabman.com, Muslim hipsters can buy T-shirts with slogans like "Go Ahead, Profile Me," and "Frisk Me, I'm Muslim." Ameena Meer, a Muslim activist in New York, prefers the less provocative, "Another Muslim for Peace."

After enduring dirty looks as a medical student in Sarasota, Fla., Pakistani immigrant Azlan Tariq bought a shirt in 2005 that read: "I'm not a terrorist, I just look like one."

"I would get looks all the time, and they weren't the happy friendly looks," said Tariq, who is now in a medical resident in Chicago. "Down there I had to make the statement."

Tariq still has the shirt, but doesn't wear it much anymore -- there's less need for it in Chicago, he said, and in a way, Tariq thinks he may have outgrown it.

"That was more of a phase. Now I feel like I can just talk to people," he said. "I'm a lot more confident. If people look at me curiously, I'll just say `Hi.' I don't feel I need this statement on my shirt."

Shibly said Muslim Americans have a lot to learn from Sikhs who wear turbans or Jews who wear yarmulkes without a sense of shame. If they can do it, he says, there's no reason Muslims can't.

"Why are other groups not afraid to show their identity, and we're so afraid?" he asked. "If we're so ashamed of it and we're trying to hide it, people will respect us less. I really believe that when you're proud of your identity and you stand-up for your culture, people respect you more."