They heard the voice crackle in their headphones. “Okay, it’s coming up now.” Straining their eyes, they saw it: way out on the horizon, barely perceptible but growing more distinct as they approached.

The vast concrete barrier stretched across the landscape, dividing the cloud-streaked dome of the sky from the green plains below. They had seen pictures, of course—everyone had—but it was always a shock to glimpse it in person for the first time. The pilot smirked as the tourists registered their surprise with a chorus of Wahs! and Aiyos!

“Isn’t it a beaut?” said the pilot. “1,300 miles of concrete, all the way from the Canadian border to the Gulf of Mexico.”

Only one of the passengers understood what the pilot was saying, and he translated for the rest, who nodded absently as they stared out the window.

The Wall drew closer as the chopper soared over the rural checkerboard. “Now, I know what you’re thinking and you’re right: it’s not as long as the Great Wall. Not even close. You could say that what it lacks in length it makes up for in height.”

After a while, they could see it clearly, gleaming deathly white: massive, almost geological, rising 800 feet from the earth. Automated machine gun turrets lined the top.

The pilot pulled up on the stick to his left and the chopper started to climb. “The Wall is 200 feet thick in most places. Over one trillion cubic feet of super-strong fiber-reinforced concrete, weighing a total of over 82 billion tons. I shit you not—excuse my French—but that’s about half the weight of Mount Everest.”

More Wahs as the Chinese took it all in.

“The most amazing thing is how fast it was all built. Nobody believed it could be done during Solomon’s administration, but it only took six years from groundbreaking ‘til the last dollop of concrete was poured. Where there’s a will, there’s a way. ‘Course, that’s probably slow by your standards.”

The helicopter now hovered over the gray ribbon of Interstate 70, which ran for another mile before it met the brutal expanse of the Wall at a right angle. As the chopper climbed, the passengers could see beyond the mighty barrier, to the plains of Kansas that stretched away on the other side. The deserted strip of I-70 continued on the far side of the Wall, running straight ahead to the western horizon.

“Okay, now listen carefully, folks,” the pilot announced. “I know you all paid top dollar to be here, and you will get your money’s worth. But there is something you need to understand. What you are about to see may…disturb you. God knows it disturbed the hell out of me the first few times I saw it.”

The young billionaire from Shanghai, who wore aviators and a tailored spray jacket, repeated the message for his traveling companions. His wife nodded, a pretty woman who seemed to be dressed for a tennis match.

“So if you feel scared or sick, I want you to close your eyes,” the pilot continued. “Close your eyes! The last thing we want is for you to have a panic attack in the air. You’ll ruin the experience for everyone else.”

“We get it,” said the Shanghai man, his voice tense with anticipation. He had raised $4 billion for a food delivery app.

“Good,” said the pilot. He lifted the binoculars to his face and adjusted the focus. There. The dark mass approaching on I-70, way off in the distance.

The pilot squinted at the shambolic procession, and felt a familiar chill down his spine.

“Yep,” he muttered to himself. “Right on schedule.”

For two years now, the hordes had been marching. They drew their numbers from across the Democratic States of America, from the filthy tent cities of California to the hipster enclaves of Colorado, from the slums of Seattle to the chaotic border towns of Texas. They gathered slowly, obscurely: tens and hundreds of thousands of the desperate and dysfunctional, packing up what little they could carry and heading east. Those who had cars drove, but most hitchhiked, used public transportation, or simply walked the distance. And as they approached the Wall, their numbers swelled.

In Kansas, the diffuse tide of migrants from across the land assembled and crystallized into a coherent force, which launched itself at the Wall like a giant human battering ram. Wave after wave of men, women, and transfolk approached the towering concrete edifice, some of them sprinting as they ululated with savage joy, others trudging silently to their fate.

It was not entirely clear why they did it. Presumably, some hoped that they might actually get through the Wall; that if enough of them converged on the barrier at the same time, they could somehow provoke fear or pity in the Wall’s masters, and they would be let in.

If that was their hope, it was always vain, because every single person who came within 1,000 feet of the Wall was immediately mowed down by the sentry guns.

“Now, I have a theory,” said the pilot as the chopper banked left and flew parallel to the Wall. “Back in the Air Force, we had to study military strategy. We learned about this dude named John Boyd. Long story short, Boyd argued there were three levels of warfare: the physical, the mental, and the moral. Am I boring you?”

But the six passengers were silent, their gazes fixed upon the landscape beyond the Wall. There, the pilot knew, they could make out the kill zone. An ugly sight.

“Anyway,” he continued, “the idea is that the moral level trumps the mental level, and the mental trumps the physical. Example: if I slaughter a bunch of enemy civilians, I’ve won a physical victory, but now I’ve turned the whole population against me, and maybe my own population, too. Maybe they revolt. That’s a moral defeat. Strategically, the joke’s on me.”

The tourists gaped as they took in the large swath of discolored earth running parallel to the far side of the Wall. In it, they could make out the seemingly limitless pile of mangled and severed human corpses, the gleam of white bones in the sunlight. The dull stain of blood across the blasted ground. Bullet-ridden vagina hats and torn, scattered rainbow flags.

“So these whackadoodles who fling themselves at the Wall like it’s going out of style. Like there’s any chance at all they’re getting in. What are they thinking?”

The mogul from Shanghai had an SLR with a telephoto lens and was furiously taking pictures. His wife gripped his arm, wide-eyed.

“I couldn’t figure it out,” the pilot was saying. “Saw it happen over and over again, like some nightmare version of Ellis Island where Lady Liberty has a robot gun and she just lays into those huddled masses, cuts them down like wheat.”

The oncoming horde was closer now, its dimensions visible to the occupants of the chopper. It was a sight that would have gladdened the heart of a bureaucrat or civil rights activist in the olden times, before the Partition: hundreds of thousands of needy migrants tumbling down the Interstate like a vast mobile favela. Cars and trucks picked their way through the heaving mass, while news choppers buzzed overhead.

“And then I had a brainstorm. Those fuckers that Solomon kicked out; they’re crazy, but they’re not stupid. Not their leaders, anyway. What if they’re playing the long game? What if, by provoking us to butcher them, they win on the moral level?”

Now the chopper had looped around and was retracing its path along the Wall. They couldn’t fly over the Wall, of course; they would be shot down instantly. But they could get close enough to see the action unfolding on the battered plain below.

“That’s why we installed the sentry guns, mind you. Fully automated, triggered by sensors; takes the human agency out of the process. So the people of the Republic aren’t overwhelmed with guilt.”

The pilot picked up the binoculars again and studied the arriving horde, which was beginning to dissolve as the people in front broke into a headlong sprint.

“Not that the people give much of a shit anyway. Our cuck days are over.”

The Chinese tourists gasped as the great warning beacons atop the Wall began to flash and they heard the unearthly wail of the siren. A few minutes later came the dull roar of the guns as the vanguard of the horde reached the kill zone.

“I know it’s tough to watch,” the pilot yelled. “We don’t have to stay for this.”

He was, he realized, speaking to himself. The four middle-aged tycoons were pointing out the window and chattering excitedly to each other. The app billionaire was taking a selfie with his iPhone held aloft while his wife, head touching his, made a flirtatious V sign. It was a good shot, as it turned out; the ironic juxtaposition with the carnage with the background with the playful expressions of the couple showed a budding artistic sensibility.