When I last spoke to Dennis Mileti, one of the world’s leading experts on how humans behave in disasters, he told me he was frightened. It was March 19, 2020, the dawn of the pandemic, and I didn’t know what to make of it. In 16 years of interviewing him as a reporter, I’d never heard him say he was scared. Not after 9/11, not after Hurricane Katrina.

Mileti was frightened not because he thought he was going to die. Like most of us, he told himself he’d be spared. “Of course, I don’t believe I’m going to get it and die,” he told me, laughing at himself, “because I’m a human being and process risk like anyone else.”

No, he was worried for the country. It had been only eight days since the World Health Organization had declared a pandemic, but he could already see that the government was failing to properly respond. “When I stop thinking and just lay in the quiet, I get really scared,” he said.

Mileti died of covid-19 on Jan. 31. We’ll never know how many people could have been saved if authorities had followed the disaster communication guidance that Mileti helped develop as the head of the Natural Hazards Center at the University of Colorado at Boulder. We just know that guidance was not followed. Going into this catastrophe, we had many preexisting conditions: a hyperpolarized country; decentralized, inequitable health care and education systems; and a president who showed little loyalty to the truth or to science.

Mileti could see what was coming in a way I could not. “We have people saying, ‘It will be over soon!’ and other people saying, ‘It could be months,’” he said back then. “That gives the public the ability to pick the answer they like, which is the No. 1 no-no in public messaging.” I’d never heard him be particularly partisan, but he was profoundly disappointed by the politicized federal response. “The feds are just an embarrassment. … If you don’t know what you’re doing, don’t do it.”

As he predicted, people picked only the messages they wanted to hear — about the need for masks, about the timeline for a vaccine, about whether schools should reopen. This included certain governors, school districts — and of course the then-president — and contributed to a crazy quilt of conflicting, incoherent policies, more public distrust, conspiracy theories and runaway blame.

Mileti wasn’t dour: He delighted in provoking people to get them to change. I remember watching him speak at a disaster research conference shortly after Hurricane Katrina. He wore a Hawaiian shirt and brought no PowerPoint slides. There were 400 experts in the room, and when it was his turn to talk, he stood up and started preaching about the hurricane.

“How many people do you need to see pounding through their roofs before we tell them how high the floodwaters can be? How many citizens must die to get us to do it?” he said, his voice rising. “If you can’t create the political will, do it anyway.”

Mileti did serious quantitative research, but he also knew how to talk so people would listen. He understood that emotion, social networks and group identity matter more than most things in disaster planning. He also knew that people, being human and complicated, would need to tailor their plans to their personal needs. (After he retired to the California desert, for example, his own earthquake preparedness kit included a bottle of gin, a tiny ice cube maker and an electric generator, because he knew he’d need a martini if he survived.)

“He always kept his eye on the people,” says Monica Schoch-Spana at the Johns Hopkins Center for Health Security, on “what would motivate people to put themselves out of harm’s way.”

If he were still alive today, Mileti would urge authorities to admit what they don’t know. To roll out the vaccines according to how humans actually are wired, not how we wish they were. To listen to people to understand their fears — before you tell them what to do. Then make all public directives as specific, consistent and clear as possible. And be sure those messages come from many different sources, especially now, when trust is so rare.

Last year, I didn’t quote Mileti saying he was frightened. I quoted him saying other things. Because the truth is, I didn’t want to hear it back then. I was still in denial myself — which is the typical first response to every disaster.

Mileti died two days before his covid vaccination appointment, according to Lori Peek, the current head of the Natural Hazards Center. For the rest of us, there is still time to honor his life by following his advice. To spend as much time and money investigating our sociology as we do developing vaccines.

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