Following a successful revolution, Mars has finally gained independence from Earth in Blue Mars, the final volume of Kim Stanley Robinson's Mars trilogy. But longstanding internal divisions are threatening the planet, and a major battle ensues between the radical Red faction attempting to destroy the Mars space elevator -- and further sever ties with Earth -- and a group of Greens trying to stop them. (The Reds want to preserve Mars in its original state, while the Greens favor terraforming.)

In the battle's aftermath, Sax Russell, a leading scientist of the terraforming effort, tries to smooth tensions by removing the soletta -- a collection of orbital mirrors -- from Mars orbit. Even though the loss of the soletta may cause an ice age on Mars, Russell feels it's a necessary tradeoff to recognize the efforts of Ann Clayborne -- the original Red -- who tried to prevent the battle.

This incident spurs the various rival political factions to agree on a joint meeting to create a Mars constitution. At the same time they send a delegation to Earth, which is in the midst of a natural disaster. Volcanoes in Antarctica have erupted, melting part of Earth's southern ice cap and raising ocean levels seven meters. Earth was already severely overpopulated and polluted, and this new environmental crisis has turned billions of people into refugees. Part of what Earth wants from Mars is a guaranteed level of immigration, a demand that sets off new conflicts for the citizens of the red planet.

Though there are many other subplots, Blue Mars focuses much of its attention on the emerging Martian political scene and its relationship with Earth, on Sax's sudden obsession with finding a way to please his old adversary, Ann, and on the aging of the First Hundred settlers as adverse long-term effects emerge from the longevity treatments developed in Red Mars. Robinson is as meticulous with his details as ever, whether he's describing the mechanisms of memory, the political and economic theories behind the new Martian constitution, or his characters' internal emotional and mental struggles.

In Blue Mars it becomes clear that Robinson is writing about humanity's next great cultural leap as much as he is writing about the colonization of Mars. Earth, dominated politically and economically by corrupt metanational corporations, is declining toward a dark age. The Martians, invigorated by both necessity and opportunity, have quickly become the intellectual and technological center of humanity. It's an age with many parallels to the Renaissance as scientific discoveries abound in the new social climate, and Robinson convincingly transforms both political and economic structures. By the end, the synergies enable not just the colonization of the rest of the solar system, but also the first expeditions to the stars.

Blue Mars concludes a truly remarkable intellectual achievement. Robinson has set a new standard for realism and complexity in the exploration of the future that likely very few will try to match.