Free society will survive terrorism. John McPhee wrote, in The Curve of Binding Energy (1973):
To many people who have participated professionally in the advancement of the nuclear age, it seems not just possible but more and more apparent that nuclear explosions will again take place in cities. ... What will happen when the explosions come --- when a part of New York or Cairo or Adelaide has been hollowed out by a device in the kiloton range? Since even a so-called fizzle yield could kill a number of thousands of people, how many nuclear detonations can the world tolerate?
Answers --- again from professional people --- vary, but many will say that while there is necessarily a limit to the amount of nuclear destruction society can tolerate, the limit is certainly not zero. Remarks by, for example, contemporary chemists, physicists, and engineers go like this (the segments of dialogue are assembled but not invented):
"I think we have to live with the expectation that once every four or five years a nuclear explosion will take place and kill a lot of people."
"What fraction of a society has to be knocked out to make it collapse? We have some benchmarks. None collapsed in the Second World War."
"The largest bomb that has ever been exploded anywhere was sixty megatons, and that is one-thousandth the force of an earthquake, one-thousandth the force of a hurricane. We have lived with earthquakes and hurricanes for a long time."
"It is often assumed that a full-blown nuclear war would be the end of life on earth. That is far from the truth. To end life on earth would take at least a thousand times the total yield of all the nuclear explosives existing in the world, and probably a lot more."
"After a bomb goes off, and the fire ends, quiet descends again, and life continues."
"At the start of the First World War, the high-explosive shell was described as 'the ultimate weapon.' It was said that the war could not last more than two weeks. Then they discovered dirt. They found they could get away from the high-explosive shell in trenches. When hijackers start holding up whole nations and exploding nuclear bombs, we must again discover dirt. We can live with these bombs. The power of dirt will be reexploited."
"There is an intensity that society can tolerate. This means that x number could die with y frequency in nuclear blasts and society would absorb it. This is really true. Ten x and ten y might go beyond the intensity limit."
"I can imagine a rash of these things happening. I can imagine --- in the worst situation --- hundreds of explosions a year."
"I see no way of anything happening where the rubric of society would collapse, where the majority of the human race would just curl up its toes and not care what happens after that. The collective human spirit is more powerful than all the bombs we have. Even if quite a few nuclear explosions go off and they become part of our existence, civilization won't collapse. We will adapt. We will go on. But the whole thing is so unpleasant. It is worth moving mountains, if we have to, to avoid it."
And near the end of The Curve of Binding Energy, McPhee and Theodore Taylor (former nuclear weapon designer) are on the road together:
Driving down from Peekskill, another time, we found ourselves on Manhattan's West Side Highway just at sunset and the beginning of dusk. There ahead of us several miles, and seeming to rise right out of the road, were the two towers of the World Trade Center, windows blazing with interior light and with red reflected streaks from the sunset over New Jersey. We had been heading for midtown but impulsively kept going, drawn irresistibly toward two of the tallest buildings in the world. We went down the Chambers Street ramp and parked, in a devastation of rubble, beside the Hudson River. Across the water, in New Jersey, the Colgate sign, a huge neon clock as red as the sky, said 6:15. We looked up the west wall of the nearer tower. From so close, so narrow an angle, there was nothing at the top to arrest the eye, and the building seemed to be some sort of probe touching the earth from the darkness of space. "What an artifact that is!" Taylor said, and he walked to the base and paced it off. We went inside, into a wide, uncolumned lobby. The building was standing on its glass-and-steel walls and on its elevator core. Neither of us had been there before. We got into an elevator. He pressed, at random, 40. We rode upward in a silence broken only by the muffled whoosh of air and machinery and by Taylor's describing where the most effective place for a nuclear bomb would be.
We went down a stairway a flight or two and out onto an unfinished floor. Piles of construction materials were here and there, but otherwise the space was empty, from the elevator core to the glass façade. "I can't think in detail about this subject, considering what would happen to people, without getting very upset and not wanting to consider it at all," Taylor said. ... Walking to a window of the eastern wall, he looked across a space of about six hundred feet, past the other Trade Center tower, to a neighboring building, at 1 Liberty Plaza. "Through free air, a kiloton bomb will send a lethal dose of immediate radiation up to half a mile," he went on. "Or, up to a thousand feet, you'd be killed by projectiles. Anyone in an office facing the Trade Center would die. People in that building over there would get it in every conceivable way. Gamma rays would get them first. Next comes visible light. Next the neutrons. Then the air shock. Then missiles. Unvaporized concrete would go out of here at the speed of a rifle shot. A steel-and-concrete missile flux would go out one mile and would include in all maybe a tenth the weight of the building, about five thousand tons." He pressed up against the glass and looked far down to the plaza between the towers. "If you exploded a bomb down there, you could conceivably wind up with the World Trade Center's two buildings leaning against each other and still standing," he said. "There's no question at all that if someone were to place a half-kiloton bomb on the front steps where we came in, the building would fall into the river."