1)Decimation. Any Congressperson voting for military action must prove their belief that it is necessary for Americans to die in combat by subjecting themselves to decimation, by the classical Roman model. All those voting for mlitary action are placed in a pool, 10% are chosen at random and immediately executed. If it is necessary for Americans to die for political ends, let Congress put their money where their mouth is.
2)Service. Only persons who have served their country (including non-military service such as VISTA, the Peace Corps, the old CCC, etc.) may hold public office. Or (following Heinlein's "Starship Troopers") even be able to vote. National Guard-hiding vermin such as "W - the President" would still be in, but Dick, Rummy, and the rest of the chicken hawks would be out.
3)Lottery. Make all military budget items be funded by a lottery. Ticket holders would be eligible for prizes - or service in combat units. I wonder how many tickets they'd sell?