John Kerry always wanted to win the Congressional Medal of Honor, so I guess his confusion is for the purpose of winning another medal he didn't earn.
Notice that Bob Kerrey, who really was a war hero, doesn't like talking about the war, and doesn't like talking about his medals. The men who earned their medals know that the real heroes were the guys who didn't make it back, the guys who took a bullet for their buddies, the guys on the Wall.
In the next paragraph, p. 72: "Kerry could not help but sense the irony of his being a war hero, since he had not wanted to fight in the war at all... ...Though he questioned the policy behind the war, he did not see either jail or exile as a reasonable alternative for himself; besides, he says he 'believed very strongly in the code of service to one's country.' So he enlisted in the Navy, to see for himself what was going on and at the same time to stay out of combat. To that end, he volunteered for assignment on one of the swift boats--short, fast aluminum craft that were used for patrol duty off the Vietnam coast. Two weeks before he arrived in Vietnam, the Navy began changing the deployment of the boats, sending them up the rivers instead to ferret out pockets of Viet Cong that were guarding the waterways for their own use."