Moments after the AR-15 assault at Marjory Stoneman Douglas High School hit the news, emails and social media alerts pinged in my in-box. I wrote a biography of the school’s namesake several years ago, and people were messaging to express their horror over what had happened. A secondary concern of some was that the good name of Douglas, one of our late, great citizens of Florida, would become, like Columbine and Sandy Hook, synonymous with gun violence tragedy.I have come to see the issue differently. Too many names on too many public buildings either belong to an unsavory or obscure figure of the past. The unsavory ones — a Confederate slaveholder or Indian fighter — stir up controversy. The obscure ones hang as meaningless labels without social context or value. But Douglas, who lived to be 108, had an enduring public life, one that resonates in a positive way with what happened at the school named for her. For one, she never shied from brutal truths.What shifted my perspective of Douglas’ relationship to events was the cage-rattling "BS" speech Emma Gonzalez gave three days after the shooting. The students had risen up. If Douglas were around today, she would find their response to gun-control complacency inspiring. In turn, whether the students know it or not, their initiative is in keeping with Douglas’ legacy.Most people remember Douglas as the pearl-necklaced icon of Florida environmentalism, the wicked-smart, take-no-prisoners spokesperson of the original movement to protect the Everglades. But the green matriarch was only one side to her long and complex life, and not the side to which she identified most closely. All her adult life, she was first and foremost a defender of social justice.The last public speech she gave, in 1989 at age 99, was on women’s rights. For decades, she denounced Big Ag’s practice of subjecting immigrant and migrant labor to concentration-camp-like living and working conditions. When others complained about the Cuban "invasion" of Miami, and fled, she celebrated its Latin transformation. After a communist witch hunt in the city in the 1950s turned anti-Semitic and anti-black, she became a founding board member of the first ACLU chapter organized in the South. She composed a poem in the 1920s that helped bring an end to convict leasing in Florida, and wrote a play performed on the national stage exposing the death penalty as a sham. She penned countless columns deploring the hypocrisy of political leaders. Too many of them, she once wrote, run for office who were "obviously built to walk."She also knew what it was like to be snubbed by state lawmakers, as were Douglas High students recently when state House representatives voted resoundingly against considering a ban on assault weapons. In 1917, after Douglas and sister suffragists returned from a fruitless lobbying trip to the state Capitol, she remarked: "We could have been talking to a bunch of dead mackerel, for all the response we got."But Douglas was invigorated rather than dispirited. She returned to Tallahassee many more times to berate lawmakers for their inaction (they did not officially endorse a woman’s right to vote until 1969). She never avoided a showdown with anyone. She could "take the heat," as she said when insults, slurs and lies were cast against her, because she believed deeply in her cause.The Douglas High students have shown their own resolve. Gun advocates, conspiracy theorists and run-of-the-mill thugs have assaulted and harassed them online. But they are likely to endure. As one tweeted, "You can’t stop us, you never will and you never can, we have the strength and grit to last far longer than these politicians." The student groundswell has lifted beyond a fly-by-night protest to the level of a cause, one showing the potential of expanding into a historic movement for citizens’ rights against gun violence. When Douglas was sensing her end, she said, the "most important thing is to prepare competent people to follow you." She trusted young people to carry on.She had inspired many, and believed in their potential. Those at Douglas High are living up to theirs. It was born from tragedy and out of their hearts. Their competence is sure, and their cause just. It is the animating force of their extraordinary initiative. Their inspiration comes from within, but if ever they need a morale lift or guidance from the past, they need only to look at the person behind their school’s name.Jack E. Davis is a professor of history at the University of Florida. His latest book, "The Gulf: The Making of an American Sea," is the winner of the 2017 Kirkus Prize for nonfiction and is a finalist for the 2018 National Book Critics Circle award for nonfiction.