SUMMARY: The time is the late 21st century. There has been a third world war, and America and the world has more or less recovered from the aftermath. But America is transformed into a near-fascist state... The novel involves a race by the three powers (America, Europe, and Asia) to re-establish contact with a colony established on Alpha Centauri's main planet--the colony had been jointly established prior to the war. The Americans arrive first, and the clash between the Americans and the colonists is the central theme of the book. The main notion of the book is that people and nations carry their prejudices from generation to generation, and that it may take some form of "fresh start" to eliminate these prejudices... [review by Roger J. Buffington on Amazon]
This is hard science with some very plausible advanced technology and weaponry. Hogan gets a little heavy-handed at times, but he tells a rousing story.
From back cover: INVASION FROM EARTH Earth seemed doomed to a fiery death, so they colonized the Alpha Centauri system with children. But not everyone perished in Old Earth's War. Decades later a generation ship bearing a cargo of colonists--and an army to protect them--headed for the planet Chiron to reassert Earth's lawful control over the fledgling colony.
Too bad the colonists didn't see things the same way.
A deadly clash--with supermodern weapons--was inevitable as each faction sought to convert the other to the 'right' way.