Terroristic acts and murder remain heinous crimes regardless of the occupation of the victim. This reminds me of the Witnesss. For your information, I could well be a diplomat or U.S. Attorney. September 11th was not fun. The people who died at Ground Zero and the Pentagon were not evil. Public law views military action in the field as different from sitting at a base.
The U.S. military is not an evil force. The service people do not make foregin policy. They follow orders. The New York Police Department officers saved me from death or serious bodily injury many times. If you don't like policy, write to the U.S. President or the mayor. They are paid fairly well and have the glamour. Complain to members of Congress. It is their job. Service people do not exist to be murdered by a thug.