Ghosts of War

While the book has just started there are certain mentalities of this high school student who was sitting in class when the planes hit the towers.  He knew that the country was going to war over this but that was when he decided that he was going to join the military.  "If I don't do it, then who will." this is probably what many people in that age group was thinking after the towers fell that if they do not act then nobody else will.  Why does a student who could go into many other fields of study in college decide that, knowing that a massive war is going to breakout at some point, join the military reserves? Nationalism,  when something happens to the country we live in, some people feel like the military is the only option. In american studies we read an article by Barbara Kingsolver that said nationalism destroys countries and people as soon as muslims were targeted, a man went out shooting at other neighbors who were foreign born. Is this situation the same? Is he going into the Army to protect the country or to seek vengeance against the people who did this crime?