Story highlights Gap ad featuring Sikh designer and actor Waris Ahluwalia was defaced

A photo of the defaced ad went viral and Gap responded

Valarie Kaur: "People can 'make love' in response to hate"

This holiday season, an ad campaign is selling clothes and challenging bigotry in America.

poster of a turbaned and bearded man in Gap clothes with a woman hanging on his shoulder hit store windows and subway walls across the United States last month as part of Gap's "Make Love" ad campaign. The model is Waris Ahluwalia, a Sikh actor whose turban and beard is part of his faith.

For the first time, a mainstream, nationwide ad presents a turbaned man as beautiful, even sexy. He is not a suspect, but a model; not a terrorist, but a person with dignity; not a foreigner, but an American.

The ad thrilled Sikh Americans like me, who have worked for years to dismantle one of the most pernicious prevailing stereotypes in American culture: turban equals terrorist.

Valarie Kaur

Nearly every person who wears a turban in the United States is Sikh. Many Sikhs wear five articles of faith, including kesh, long uncut hair that most men and some women wrap in a cloth turban. Tragically, the turban meant to represent a commitment to service and justice marked Sikh Americans as targets of hate.

Recently, the ad featuring Waris Ahluwalia was found covered with racist graffiti on a New York City subway wall . "Make Love" was crossed out to read "Make Bombs." Someone scrawled beneath it, "Please stop driving TAXIS."

The racial epithets were familiar, but what happened next was altogether new. The photograph went viral on Twitter . Within 24 hours, Gap set out to replace the defaced ads, made the ad its background image on Twitter and Facebook and released the statement, "Gap is a brand that celebrates inclusion and diversity." The company's response set off a chorus of #ThankYouGap posts.

The story is a powerful example of how a groundswell of people can "make love" in response to hate. It's a story we need now more than ever.

Twelve years after September 11, 2001, the stereotype of the turbaned and bearded terrorist is deeply entrenched in our social imagination. It shows up in profiling at airports, bullying in the school yard, violence on the streets, surveillance of houses of worship , and yes, graffiti on a New York City subway wall.

In daily encounters, our minds default to stereotypes we have unwittingly absorbed. The most dangerous racial stereotypes trigger fear and animosity -- for example, African-Americans as "criminal," Latinos as "illegal," or Muslims and Sikhs as "terrorist." Once a person is reduced to a stereotype, it becomes easier to harm them, or to permit harm to be done to them.

But there is a powerful antidote to these stereotypes: the diversity of faces, voices and stories of real people that show our shared humanity.

In the aftermath of the 2012 mass shooting in a Sikh gurdwara in Oak Creek, Wisconsin , thousands of people wrote heartfelt letters in an outpouring of love and support to families who lost loved ones and signed petitions that led to a new government policy to track hate crimes against Sikhs.

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This fall, after Columbia University professor Prabhjot Singh was brutally beaten in New York City , nearly 4,000 people of different faiths sent him prayers and messages online.

And 11 days ago, when photographer Robert Gerhardt, a white Catholic, saw racist graffiti covering a photograph of a Sikh, he chose to take a photograph of the ad. He sent the photo to Muslim American writer Arsalan Iftikhar, who decided to post it on Twitter. Others shared the photo, which prompted Gap to take a public stand.

Earlier this month, Gap employee Casey David Muir-Taylor made the same choice when an irate customer complained about the Muslim "terrorist" in the "do-rag." He defended the ad and posted about it on Facebook . Each of these individuals chose to fight for a community not their own.

As a Sikh American, these acts of courage deepen my commitment to do the same for others.

Companies should take note that taking a public stand against hate wins new customers.

But it would be a mistake to miss the deeper lesson: We as individuals can no longer claim helplessness in the face of racism. In the digital era, the power to "make love," not bigotry, lies in the palm of our hands. Whether in response to a Sikh model in a fashion ad, or a South Asian American woman crowned Ms. America , new media give a new generation a chance to speak out for our vision of America.

The key is using our power to dismantle the stereotypes that shape our social landscape.