Starship Troopers by Robert A. Heinlein
Earth is caught in the midst of a deadly conflict with the implacable Arachnids, a swarm of insect-like aliens intent on wiping out all human life. Fresh recruit Juan ‘Johnny’ Rico signs up impulsively, keen to prove himself in the upper echelons of the Navy. Instead he finds himself assigned to the Mobile Infantry, the frantic and hardcore frontline where all that stands between life and an alien death is a sophisticated armored suit. Thrown into a training program that may well kill him before he even gets a crack at the ‘bugs’, Johnny’s destiny lies in war-torn space.