Maybe you don't want to read this story, because, really, who wants to think about frightening what-ifs?
But this week, the FBI Minneapolis office tweeted out an advisory about active-shooter situations: "Take time now to think about how you'll react."
Before the Las Vegas attack, there was the bombing at an Ariana Grande concert in Manchester and the mass shootings at a concert in Paris and the Pulse nightclub in Orlando. So it's worth thinking about what you'd do if an attack occurred at an entertainment venue closer to home.
At Treasure Island Resort and Casino, near Red Wing, flags were flying at half-staff Wednesday to honor those killed in Las Vegas.
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"Obviously, it's a horrific event, and it's on everyone's mind," said Daniel Johnson, head of security for Treasure Island. "Hopefully we'll all learn from their horrific experience and adapt accordingly."
As he walked the halls of the casino and resort, Johnson said his job is to study the environment daily, to consider every planned event and to mitigate all plausible scenarios — a fire, a bomb threat, an active shooter.
But he said those who happen to be present in an emergency share an element of personal responsibility, too.
"So what can you do, as an ordinary citizen, or attendee, or a guest?" he asked. "What can you do to poise yourself in a position of personal preparedness, whether it's here or anywhere?"
For starters, he said, it's important to know your environment. It doesn't matter if you're at work, a shopping mall, a movie theater or an outdoor concert: Know the nearest exits.
"Know where to go if something bad happens, because obviously your role as an attendee on our property is to flee when something bad happens," he said. "We want you to get out of harm's way."
At the Advanced Law Enforcement Rapid Response Training Center at Texas State University, students learn a system called Avoid, Deny and Defend.
Pete Blair, the executive director, said the idea is to stay hidden from a shooter, finding a cover or structure that can stop bullets. Then, if possible, deny access or entry to the assailant. And finally, defend yourself, and attack if someone is trying to kill you.
He added that it's unwise to play dead.
"We advise against freezing or playing dead," he said. "And the reason for that is we see over and over again, in these active-shooter events, that after the attacker shoots people who are up and moving around, they then start to shoot people who are down, in order to make sure that they are in fact dead.
"Additionally, in a concert venue like that, if you drop to the ground, you're risking being trampled."
Blair said that in the Las Vegas shooting, he's hearing about many civilians who saved lives by taking the injured to hospitals. He suggests that people also learn about the government's "Stop the Bleed" campaign, which trains civilians in simple techniques to control hemorrhaging so that a person can survive long enough to get to a higher level of care.