Lieutenant Cross is the leader of the troop that goes to Vietnam which O’Brien is part of. Though the reader can only deduce that he should lead the troop, no definite role is attached to him that a reader can openly say. It is assumed that he should give the rest of the troop direction on what to do as they wage war on the enemies and have a chance to defeat them.
He comes out as a weak leader. This is demonstrated by the fact that he does not give any clear strategy on how the war can be won. All he is concerned about are the normal things like how the soldiers can match in a straight file and how to keep the weapons clean. There is no situation where he advises how the soldiers can adapt to the difficult terrain they find in the war zone. The only thing that gives him authority over the rest of the platoon is that he has a higher rank. At the same time, he keeps himself away from the rest of the people so that they do not disrespect him.
Cross is also emotional. There is a photo of Martha, his girlfriend that he keeps looking at it. This is a way to keep a close link with his lover. That character is not good in a war situation. It is even worse when you are supposed to lead others while fighting the enemy. As a leader, he is supposed to be strong and guide others on what to do. That is something he is unable to do as he is weaker than the others emotionally.
He is also easily distractible. It can be seen that he is more obsessed with the pebble he received from Martha as opposed to the war. There are cases of soldiers that die when Cross is distracted as he had put the pebble n his mouth.
Jimmy can also be said to be remorseful. He feels bad because Koiwa dies because he is distracted because of the distraction of the pebble in his mouth. It is at that point that he throws the pebble away as much as it was a gift from his girlfriend. That means he is someone that can take responsibility when things go wrong.
He is an understanding individual. Although Rat Riley shoots himself in the foot to avoid more responsibilities of the war, Cross understands his situation. Finally, Rat is allowed to leave.