Transcript for Marjory Stoneman Douglas students return to campus this week after deadly shooting
Reporter: For students and teachers returning this week to Stoneman Douglas high school -- Coming back to where everything occurred. It's just scary. Reporter: There's no such thing as getting back to Normal. Not after the massacre that left 17 members of their community dead. We're almost there. Reporter: This weekend an orientation for returning students. Their first moments back on campus Sunday felt haunted. I cannot stop looking at that building. I cannot stop imagining what was going on inside that building. It tears me up inside. Reporter: The grief and horror are still fresh in parknd, as they once were in columbine and Newtown and so many other communities. So many shootings, so little change. Is it naive to hope this might be the "Me too" moment for gun violence? We'll turn our grief into action. We have to have action. Reporter: At the white house today president trump met with members of the national governors association. The president imagining himself as the hero. I really believe I'd run in there even if I didn't have a weapon. And I think most of the people in this room would have done that too. Reporter: Of course the school resources officer who was there and who did have a weapon did not go in. The president's called him a coward. Today Scot Peterson, who resigned last week, responded with his side of the story. In a statement from his lawyer he claimed that he and the school security officer ran outside to respond to reports of a firecracker near the building. Once there they heard gunshots but believed that those gunshots were originating from outside of any of the buildings on the school campus. After that the statement says Peterson did what he was trained to do, taking up a tactical position nearby and coordinating with law enforcement as they arrived. "Let there be no mistake, Mr. Peterson wishes he could have prevented the untimely passion of the 17 victims on that day, and his heart goes out to the families of the victims in their time of need. However, the allegations that Mr. Peterson was a coward and that his performance under the circumstances failed to meet the standards of police officers are patently untrue." Schools across the country are reviewing their own safety procedures in the wake of parkland. Today "Nightline" was outside St. Louis, where the o'fallon police department has set up a special training room to drill for active shooters. Show me your hands! You get that adrenaline dump in this because it's as real as it can get. This scenario was a response to an active shooter in a school. We methodically went through the school. We were taking out suspects as we went until eventually we ended up with a hostage situation at the end. Put the gun down! He was shot, and as he was shot he also shot the hostage. Reporter: The authorities here designed this simulation with the company vertra. Show me your hands. Reporter: They've made modifications after what happened in parkland. It's horrible timing but it was good timing to do this. Because everybody, all police officers right now and law enforcement is in that mindset of training for an active shooter. Let me see your hands. Reporter: In this simulation they're able to put an active shooter virtually on the steps of a local high school. This is modeled on real local schools that have never had an active shooter. And this principal hopes they never do. To see bodies down in front of my building, to see police officers actively firing on someone at my school, that's -- you want to think that could never happen here. But I'm sure that parkland felt the same way. Reporter: The officers wear electronic shockers. If they're hit by gunfire, the shocker goes off. I was shocked by this. And it hurts. It definitely makes you realize that -- it makes the situation even more real. Reporter: The challenge for the officers, to disable the shooter and stay alert. Are you good? I'm good. Reporter: Most active shooters are lone gunmen. But not always. Where's he at? Reporter: It's a video game, but the pressure is real. Get on the ground. Reporter: Turning every school into a possible S.W.A.T. Scenario may be a necessary response, but it doesn't change the threat. That's the bigger fight. Down on the ground now! Reporter: Speaking today to the governors, the president acknowledged that change will take courage. Don't worry about the NRA. They're on our side. You guys, half of you are so afraid of the NRA. There's nothing to be afraid of. Reporter: His ideas include banning so-called bump stocks, the accessory that the Las Vegas shooter used to modify his semi-automatic rifles to such deadly effect. Trump insists he can get rid of them even without a bill from congress. Bump stocks, we're writing that out. I'm writing that out myself. Reporter: But the bureau of alcohol, tobacco, and firearms doesn't have the authority to ban bump stocks. And it's not clear that congress will act because so many lawmakers are afraid of crossing the gun lobby. What gun owners understand is that we're in this fight for the long haul. Reporter: Richard Feldman is a former lobbyist with the NRA. He insists the NRA isn't the bad guy. We all want to keep guns out of the same hands. Why don't we actually move forward in this country and do some things that we can agree on? Reporter: President trump has also said he'd like to raise the federal minimum age for buying ar-style rifles from 18 to 21. But the NRA has pushed back hard. The 5 million members of the NRA have made their position incredibly clear. And I do want to caution people -- Reporter: Today the white house signaled that might be enough to make the president back down. In concept the president still supports it. But in terms of legislation we'd need to see what that looks like before we weigh in further. Reporter: About the only idea from the president that seems to be a hit with the gun lobby is his proposal to arm teachers. I think it would be very effective. Reporter: Trump insists he's not talking about arming every teacher. I want highly trained people that have a natural talent, like hitting a baseball or hitting a golf ball. These are really gun-adept people. Very few people would qualify. On top of being gun adept they have to go to school and they have to learn and maybe there will be a bonus given to those people. Reporter: The democratic governor of Washington state, Jay inslee, rose to confront trump. I've listened to the first grade teachers that don't want to be pistol-packing first grade teachers. We need to listen, that educators should educate and they should not be foisted upon this responsibility of packing heat in first-grade classes. So I just suggest we need a little less tweeting here, a little more listening. Reporter: A lot of Americans seem to be uncomfortable with the idea of arming teachers, including quite possibly the president's own daughter. To be honest, I don't know. I think that having a teacher who is armed, who cares deeply about her students or his students and who is capable and qualified to bear arms is not a bad idea but it's an idea that needs to be discussed. Reporter: What's especially interesting in the aftermath of parkland is the pressure being brought to bear by a new generation of activists. That activism is now raising the stakes, turning the NRA into a corporate pariah. In the past few days nearly 20 companies have ended their NRA discounts and partnerships. The challenge now for the activists I ratcheting up the pressure on the lawmakers the NRA relies on to do its bidding. If the national rifle association's membership dropped precipitously, yes, they would lose some clout. But I certainly don't see that happening. Now that you've had an entire generation of kids growing up around mass shootings and the fact that they're able -- they're starting to be able to vote explains how we're going to have this change. Kids are not going to accept this. Reporter: Of course no one can bring back the 17 souls who died at Stoneman Douglas high school. But we can all work harder to make sure they didn't die in vain. I'm David Wright for "Nightline" in New York.
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