Voice of the Whirlwind is a 1987 science fiction/mystery novel by Walter Jon Williams. It's part of a series, but I haven't read the others and found this enjoyable on its own.
from the back of the book:
In Voice of the Whirlwind, Walter Jon Williams has projected the universe of Hardwired one hundred years into the future, to a time when the Orbitals have become independent feudal states with an interstellar drive. But the one constant of humankind is political intrigue...Kirkus Reviews concludes with this: "Fast-moving, hard-driving, with a robust, well-handled plot, an unusual approach, and plenty of intriguing complications. All in all, a stirring and heartening performance." Publishers Weekly calls it "one of the best of its kind".
Steward is a Beta. A clone. His memories are fifteen years old because his Alpha never did have a brain-scan update. In those fifteen years, the entire world has changed: the orbital policorp which held his allegiance has collapsed; dozens of his friends have died in an off-planet war; an alien race has establishe relations with humanity; his wife has borne a child, and divorced him; and someone has murdered him.
Steward still has the skills that made him a perfect military commando for his bankrupt policorp sponsors of fifteen years ago. But does he have the right skills, and can he find the missing knowledge and pieces of history that will lead him to the killer of his Alpha?