After a while the ship went out of sight, and nobody ever saw it again.
The first contact Man had ever had with an intelligent alien race occurred out on the perimeter in a small quiet place a long way from home. Late in the year 2360—the exact date remains unknown—an alien force attacked and destroyed the colony at Lupus V. The wreckage and the dead were found by a mailship which flashed off screaming for the army.
When the army came it found this: Of the seventy registered colonists, thirty-one were dead. The rest, including some women and children, were missing. All technical equipment, all radios, guns, machines, even books, were also missing. The buildings had been burned, so were the bodies. Apparently the aliens had a heat ray. What else they had, nobody knew. After a few days of walking around in the ash, one soldier finally stumbled on something.
For security reasons, there was a detonator in one of the main buildings. In case of enemy attack, Security had provided a bomb to be buried in the center of each colony, because it was important to blow a whole village to hell and gone rather than let a hostile alien learn vital facts about human technology and body chemistry. There was a bomb at Lupus V too, and though it had been detonated it had not blown. The detonating wire had been cut.
In the heart of the camp, hidden from view under twelve inches of earth, the wire had been dug up and cut.
The army could not understand it and had no time to try. After five hundred years of peace and anti-war conditioning the army was small, weak and without respect. Therefore, the army did nothing but spread the news, and Man began to fall back.
In a thickening, hastening stream he came back from the hard-won stars, blowing up his homes behind him, stunned and cursing. Most of the colonists got out in time. A few, the farthest and loneliest, died in fire before the army ships could reach them. And the men in those ships, drinkers and gamblers and veterans of nothing, the dregs of a society which had grown beyond them, were for a long while the only defense Earth had.