FORT LAUDERDALE, Fla. — Hundreds of students, teachers and residents filled the terrace of the Broward County federal courthouse on Saturday, three days after a 19-year-old gunman wielding an AR-15 left 17 students and educators dead and scores more injured at nearby Marjory Stoneman Douglas High School.

Their echoing chants of “enough” and “not one more” weren’t solemn — they were seething. None, perhaps, more so than Emma Gonzalez.

“If the president wants to come up to me and tell me to my face that it was a terrible tragedy and how it should have never happened and maintain telling us that nothing is going to be done about it, I’m going to happily ask him how much money he received from the National Rifle Association,” declared Gonzalez, a senior at Douglas. “To every politician who is taking donations from the NRA, shame on you! If you actively do nothing, people will continue to end up dead.”

Typically, the public gatherings in the days following a mass shooting are solemn, prayerful events. But time and time again, the events here in the days since Wednesday’s shooting have boiled over with righteous anger.

In Gonzalez’s nearly 10-minute address — her black tank top and tightly cropped haircut barely visible behind podium microphones that stood nearly as tall — she slammed by name senators who have proposed softening gun laws. Every few moments, the senior raised her bracelet-covered right arm to wipe tears from her eyes. In her left hand she clutched her speech, written out by hand on a stack of college-ruled paper.

She led the crowd in chants of “No more BS!”

Gonzalez was one of half a dozen student speakers at the rally, many of whom noted that despite years of disciplinary issues, Nikolas Cruz, their former classmate who police say has admitted to carrying out the shooting, was able to purchase a gun.

“This isn’t just a mental health issue!” Gonzalez said, her voice breaking into a scream. “He wouldn’t have harmed that many students with a knife!”

Wednesday’s shooting in Parkland, Fla., is just the latest addition to a long list of American mass and school shootings, tracing back to Columbine High School in 1999. An ongoing Washington Post analysis has found that more than 150,000 students attending at least 170 primary or secondary schools have experienced a shooting on campus since Columbine.

“We’ve had too many national tragedies across our country, and it’s time for this to stop,” declared Stacey Kagan, Parkland’s vice mayor. “This can never happen again.”

In the moments after the shooting, much of the nation was moved by the graphic, frantic videos taken in real time by students who were inside the school. And in the days since, the students themselves — in tweets, Facebook posts, and television interviews — have been among the loudest voices demanding changes to gun laws.

“What’s going to be different this time is that the young people are going to be driving the change,” Robert Runice, the Broward County schools superintendent, said in an interview. “What I want to see happen next is that this be a continued, sustained movement that includes massive voter registration, awareness and results and legislation to deliver common-sense gun laws.”

Among the student speakers were Cameron Kasky, 17, one of the students who launched “Never Again MSD,” which has amassed nearly 35,000 followers on Facebook in just three days, and Delaney Tarr, 17, who hid in a closet during the shooting and vowed to commit the rest of her life to reforming American gun laws.

“My innocence, our innocence has been taken from us,” Tarr said tearfully. “Our childhood is gone because that man … despite being tipped off to the FBI multiple times, was able to legally purchase an AR-15. … Because of these gun laws, people that I know died. … Because of the systematic failure of our government, at every level, people are dying every day.”

Among the policy changes they urged was a federal ban on assault weapons — specifically the AR-15, which has been used in a number of mass shootings — and for the electoral defeat of politicians who take money from the National Rifle Association, the most prominent group in the powerful gun lobby.

“Never again do I want to text my mom “I love you” in fear of never getting to say it again to her face,” said Ariana Ortega, 17, who was inside the school at the time of the shooting. “Never again should parents send their children to school only for them to never return home.”

State Sen. Gary Farmer, a Democrat who represents Fort Lauderdale, told the crowd that he toured the school Friday and spoke with the police captain overseeing the investigation. Farmer said that Cruz was carrying magazines that held 30 to 40 rounds each, and that he fired a total of 160 shots — 78 of them on the school’s first floor.

“There is no need for those high-capacity magazines or these killing machines,” said Farmer, who went on to call for the creation of a federal gun registry and who decried inaction from his colleagues in Florida’s state government on gun-control legislation, which prompted furious “vote them out” chants. “And you know what’s ironic, while our elected officials fail to act, we have brave students who are leading the way.”

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