What were Woody’s reasons for joining the military?

Woody tries to see the best in situations. While Papa withdraws from the stress of the camp, Woody takes his place as head of the family. Woody rationalizes that it is in their own best interests for Japanese men join the American Army,

"I am an American citizen. America is at war....The more of us who go into the army, the sooner the war will be over, the sooner you and Mama will be out of here"