“Maybe,” he said, but I knew I’d scored a point.

“Could a human subspecies have a greater tolerance for radiation?” I asked.

“Sure. Not to the point where they can juggle isotopes, but we’ve seen a pretty big range. Some of the exposure studies after Chernobyl and Fukushima show that.”

“Enough for them to live in a postnuclear environment?”

“That would depend on where the nukes detonate, both in relation to prevailing wind and ocean currents and to actual proximity to the highest concentrations. When Chernobyl melted down everyone thought that the area around it would be a total dead zone, but we saw plant growth return much more quickly, and also the return of animals and birds. Nature loves to adapt. Now … another factor in species survival would be the number of nukes. If the Upierczi live anywhere near one of the blast zones, it’s doubtful they would be able to withstand the doses. However, if they are removed from the blast zones, it would be up to their unique biology as to how soon they could reinhabit those areas.” He paused. “We’re looking for seven nukes worldwide? That would not pose a lasting threat even to the normal human population.”

“It wouldn’t?”

“Well, I mean a bunch of people would be toast. Worst-case scenario from the five we already know of, including New Orleans, would be maybe fifty million dead from the blasts, maybe two hundred million dead in two to forty years from cancers. That’s nothing matched against the six and three quarter billion who wouldn’t die.”

“That’s ‘nothing’?”

“Try thinking big picture once in a while,” said Hu smugly.

“Are you—”I began, my voice rising.

“Don’t start,” warned Church. “We don’t have the time for it.”

I bit down on the things I wanted to say to Hu, and he was probably grinning at the other end of the phone, thinking that he’d just scored by having me yelled at by the teacher.

“What if the Upierczi stay underground?” asked Church.

“What do you mean?” I asked. “In graves or—”

“In tunnels. We have some intelligence that they live, or at least lived, in tunnels.”

“Well,” mused Hu, “rock and dirt are great insulators as long as they aren’t part of a contaminated water table or underground river.”

“In deserts?” I asked.

“Pretty good place to be. Again, though, they’d have to be away from water or, if Rasouli’s intel is right, away from the oil sands.”

“New topic,” I said. “Physiology. The Red Knight I fought was faster and stronger than me. Not just a little, either. What’s the upper range of human potential?”