Coward?

In the chapter "On the Rainy River", I thought it was very interesting how O' Brien found himself to be a coward. But while reading the chapter, he finds himslef to be a coward for another reason than expected. In this chapter he runs away and drives north toward Canada becuase he has been drafted for the war. However, while staying at these cabins on a river bordering Canada, he realizes that he can't go to Canada so he decides to go back home and go to the war. O' Brien does not label himself a coward for trying to escape. Instead, he labels himself a coward because he can't get himself to jump off the boat and swim to Canada. For him, going back home and going to Vietnam was the cowardly thing to do. At first this seems a little odd, but I can see the reasoning that O' Brien put behind this. Simply being embarrassed of not going to the war because of what people thought of him is what made him a coward. Being courageous would have meant him doing what HE thought was right.