The Great Explosion

MISSION OF EMPIRE
Earthmen had colonized hundreds of planets in the four centuries of deep space exploration—independent new civilizations founded by the discontented and adventurous of Terra.
Trouble was, they were too independent—and the Terran government had ambitions for a space empire. A giant battle cruiser went out into the starlanes, with instructions to persuade the colonial planets to join the Empire—and with a couple of thousand troops to back up the persuasion !
It looked lik...