Colonel 'Frank' Francis crouched in the West Texas sand and squinted. "What's happening, Sergeant?"

"Nothing, sir," said the sergeant while gazing through a pair of field glasses.

"Give me those!" The colonel snatched the binoculars and refocused them.

General Barnabe stood unprotected in the middle of the rock-strewn desert. The colonel had served as Barnabe's adjutant since he'd assumed command of the 1st Armored Division, but they'd been friends much longer.

"Well, he's still alive," the colonel said, to reassure himself, mostly. He examined the thing standing in front of his friend. Barnabe was no small man, but the creature towered over him. Frank had studied surveillance photos of the aliens, but it was strange to see one in person.

"It's in its defensive posture," said the colonel.

The sergeant asked, "Is that bad, sir?"

"Not necessarily," answered Frank. "They always approach any danger or uncertainty by backing into it like that."

Frank could see the hard layer of chitin covering the alien's back. He wasn't sure if 'back' was the right term for it, since the aliens nearly always walked in that direction. It had an odd, flattened 'face' on that side of its head  — two slit-eyes and a sound hole from which it emitted noises the Army linguists were unable to decipher.

One of the snipers adjusted his scope without taking his eye off it.

The general offered to shake the alien's hand as a show of peace. It seemed uncertain about what to do, since it had no arms on that side of its body. Its sound hole moved to say something the general would not be able to understand. Left hanging, Barnabe lowered his hand and simply nodded once. The alien returned that gesture.

* * *

"I don't know," said the general after he'd returned. "I wish we could understand the damn thing. It sounded angry, I think. I can't tell if it was saying, 'We come in peace' or threatening to cut off my balls and have them for breakfast."

"So, what do we do, General?" Frank asked.

"We wait, I guess. For a little while." Barnabe lowered his head and continued, "Eventually, we'll have no choice."

"No, sir. I guess not. But we're ready for a fight if it comes to that."

The two men surveyed the forces arrayed behind them. An entire division of elite fighters, rows of tanks and armored vehicles, rocket launchers, and cannon. And in the very back, the doomsday squad stood ready with even more destructive weapons.

"I hope it's enough," said Barnabe as they turned back toward the aliens. Four enormous spaceships hovered silently against the horizon.

They waited throughout the day for some sign, some reason not to wage war on the first extraterrestrials humanity had ever encountered. Just as the sun began to set, the sergeant shouted, "Sir! You need to see this!"

A single figure sprinted toward them, taking impossibly long strides across the sun-warmed sand. The snipers aimed their rifles at the alien, trigger fingers twitching as they waited for an order.

"I can't be sure it's the same alien," said Frank.

The creature charged at them, 'back' first. When it approached the halfway point, the colonel yelled, "It's going to attack!"

A shot rang out from one of the sniper rifles, followed immediately by a shouted order from Barnabe. "Hold your fire! Hold your fire, damnit!"

The alien stopped and fell to its knees for a moment, but then slowly stood again. When it turned around and faced them for the first time, the soldiers were astonished  — not because it was strange or ugly, but because it was not. From the front, the alien was eerily human. And in his arms, he carried something.

"What's he holding?" asked the colonel. "Is that a weapon?"

The alien took a few more labored steps until he reached the exact spot where he had met the general before. He dropped a large stone into the dust. Still facing them, the alien spread his arms wide, exposing his most vulnerable parts to those who would be his enemy. Then he limped back toward his brethren, leaving a thin trail of orange fluid in the white sand.

"Now what?" asked Frank.

"I think I know," Barnabe replied. He looked around and chose a suitably large rock. After lifting it with a grunt, he carried it back onto the plain and dropped it next to the one the alien had left there. Then he mimicked the gesture he'd just seen by spreading his arms as wide as possible while facing the aliens.

As Barnabe returned, three more aliens emerged, carrying rocks and walking with their vulnerable sides showing. They piled their stones atop the ones that were already there.

"First rifle platoon!" yelled the general. "Drop your weapons and grab a rock!" The soldiers looked at each other, baffled by the extraordinary order.

"Do it, now!" the colonel commanded.

After the squad had stacked their stones atop the others, the aliens responded in kind, followed by another group of humans. Soon, the aliens and humans ceased taking turns and began working together all at once to build a cairn in the middle of that desolate place. By the time darkness made it impossible to continue, the structure was as tall as five humans or three aliens. None of the soldiers knew why they'd built it, but they all felt relieved and a little proud of the accomplishment.

* * *

Frank woke Barnabe at dawn and pointed toward the alien encampment. It took the general a moment to understand what he was seeing. Which was nothing beyond the tower of rocks they had stacked in the sand.

The aliens and their spaceships were gone.

"I don't understand, sir," whispered the colonel. "What is that out there? What did we build to make them leave like that? It's just a bunch of rocks, isn't it?"

The general smiled and answered, "It's not what we built, Frank. It's that we built it together."