Kara Alaimo, an assistant professor of public relations at Hofstra University, is the author of "Pitch, Tweet, or Engage on the Street: How to Practice Global Public Relations and Strategic Communication." She was a spokeswoman for international affairs in the Treasury Department during the Obama administration. Follow her on Twitter @karaalaimo. The opinions expressed in this commentary are solely those of the author.

(CNN) On Wednesday, Dick's Sporting Goods announced in a letter from its chairman and CEO, Edward Stack, that it will stop selling weapons like the rifle used in the shooting at a Parkland, Florida, high school on February 14. The company is no longer going to sell assault-style rifles or high capacity magazines and won't sell any firearms to people who are under the age of 21. In eloquent language, Stack also called on lawmakers to enact gun reform so other companies do the same.

Kara S. Alaimo

This isn't the first time Dick's has weighed in on this debate. Dick's previously earned plaudits when it temporarily stopped selling assault rifles after the 2012 massacre at Sandy Hook Elementary School -- and then criticism when it later opened a chain called Field & Stream that sold them.

But today's letter may be a signal of something different, and I hope other CEOs are taking notes. "We have tremendous respect and admiration for the students organizing and making their voices heard regarding gun violence in schools and elsewhere in our country," said Stack. "We have heard you. The nation has heard you. We support and respect the Second Amendment, and we recognize and appreciate that the vast majority of gun owners in this country are responsible, law-abiding citizens. But we have to help solve the problem that's in front of us." Stack has also disclosed that the Parkland killer bought a shotgun at one of his stores in November -- though it wasn't the gun used in the school massacre.

If more CEOs follow Stack's lead, they're likely to not just boost their businesses, but also finally catalyze the changes in gun laws that are so long overdue in America. New research shows that corporate leaders have extraordinary power to sway public opinion on important issues. A study by Weber Shandwick , one of the world's largest communications firms, last year found that the majority of Americans -- 74% of millennials, 63% of Gen Xers and 55% of baby boomers -- have actually taken action because of a chief executive's position on an issue.

Today, Americans expect businesses to practice corporate social responsibility. This means acting as good citizens. A Cone Communications study published in May found that the majority of Americans both buy from and boycott companies based on their stances on pressing social issues. This has become a much bigger priority for consumers in recent years. For comparison, in a 1993 study by the same group, 66% of Americans said they'd switch brands to buy from a company associated with a good cause. Today, 89% say they would do so. And 63% of Americans now say they hope businesses will drive future change on social and environmental issues.

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