“It will put Portland and Seattle out of action potentially for years,” he says.

And that’s just the earthquake. Next up, in the Mother of All Disasters trifecta, another deadly piece of jargon: liquefaction. That’s when the earth shakes the sandy substrate beneath houses and fire stations and hospitals all along the coast so vigorously that the soil mixes with the high-water table beneath it, turning the ground into quicksand. So what didn’t get shaken into pieces gets swallowed up by the earth, at least in some places.

Then comes Cascadia’s final blow: the tsunami. Waves traveling at jetliner speeds across the open ocean, barely higher than the surface of the water far off shore but soaring up into the sky, 100 feet or higher, once they approach land.

Waves. Not just one wave, not just one skyscraper of a wall of water, but one after another after another, each flooding the cities along the Oregon and Washington coasts, ripping trees out by their roots and swirling them back and forth into a muddy whirlpool. Swimming skills don’t save people when they’re being pinned beneath the water by a floating bus.