ColSec Rebellion by Douglas Hill, 1985.
This is the final book in the ColSec Trilogy, a sci-fi series. The first two books are Exiles of ColSec and The Caves of Klydor.
In a future where Earth is controlled by an oppressive government, dissidents are exiled to distant planets to start colonies whose resources can be exploited by the government. However, the colonists have been plotting to take their destinies into their own hands.
Cord MaKiy and his friends, once exiled colonists on the planet Klydor, have joined up with the resistance movement. They hijack a ColSec ship and return to Earth to gather allies for the rebellion against Earth’s government, called The Organization.
Once on Earth, they turn to the societies that they came from, little groups of outcasts on the fringes of Earth’s society. Cord’s people, the Highlanders who live in the wild areas of Scotland without modern technology, welcome them, and many of the young people are interested in joining the colonies, seeing other worlds, and living in freedom. Similarly, the rebels find more friends among the Vampires, the youth gang that lives in the Bunkers (what’s left of the old subway system under London).
However, the Streeters (a youth gang in the Chicago area) are a different story. Although many of them want to escape their little hideouts in the urban jungle called Limbo, their leader, Tuller, is unwilling to give up his relatively comfortable position of power. When he betrays the rebels to the government, the others have to decide where they stand and if they’re willing to take the risks necessary to gain their freedom.
In a way, the colonists seem to gain their ultimate freedom more easily than expected, but that’s partly a product of the type of repressive government that controls Earth. It isn’t really a military dictatorship, although they do use deadly force against their enemies; it’s more of a greedy corporate structure, designed to bring vast amounts of wealth to the people at the top of the structure, while keeping the lower levels in line to do their bidding. In the end, as Lathan had guessed in the previous book, The Organization is more concerned with profit and loss than anything else, and the rebels manage to cut them a deal after showing them that fighting would only bring heavy losses with no material gain.
There’s plenty of action in the story as the young rebels struggle to prove themselves to potential allies on Earth and flee the forces of ColSec to return to Klydor, where they issue their ultimatum. The negotiations with Earth are summed up fairly quickly, and although there are no more books in the series, the ending sets it up for Cord and his friends to continue their life of exploration on other worlds, seeking out new places for people who want to flee the dull repression that still exists on Earth.