If you are in the US military, you are required to fight or kill who your governement sends you to fight or kill, independent thinking is discouraged when it comes to the morality or wrong or rightness of the conflict which the government is invovled in. I prefere not to be a fighting robot programed by the government. I don't think me making such statement requires a lot of research for it to be true.
You are only talking about you. You are not being asked to join the military. It is currently a volunteer force. You devoted a great deal of your life to what you felt was a higher goal or duty. You are understandably pissed off about how that turned out. It is possible however that other people can have what they believe is a higher call of duty...one that we may not prefer for ourselves....but we can show them the proper respect for their decision and not denegrate it because we don't understand it. The coast guard is military. I'm sure you couldn't help but feel a little something when they single handedly rescued thousands after Katrina.