Sequel to Old Man’s War.
Jared Dirac is a superhuman clone in the elite Colonial Defense Forces. A backup of the brain patterns of the traitor Charles Boutin have been implanted in his head so that his superiors can learn what happened. He can’t access those memories so he’s sent out on missions. Then the memories start trickling in.
Scalzi has constructed a scary but credible universe, where the clones can be more human than the “Realborn”.