Interplanetary Defense Force - Paperback

Corporal Mark Allen Rogers, a young man, stands his ground as the enemy attacks and most of his platoon flee the onslaught. As a reward for his heroism, he is sent to the Officer Candidate School where he learns the ropes of being an officer. There he meets another soldier, Cynthia Street, and because they are from the same brigade, they become friends.
Returned to the fleet, he is assigned as a platoon leader, taking command of a unit that had been engaged in combat operations. On one of the patrols, his platoon finds a downed enemy shuttle and Rogers makes the discovery that alters the course of the war. He is with the division, leading one of the assaults on an enemy stronghold. With luck they'll be able to learn more about the enemy, and then end the enemy threat. It doesn't go quite as planned and there is still one more twist in the war.