Military R&D has translated into the rapid advancement of civilian commercial applications that benefits not only the US but everyone else in the world, friend or foe. If you have a new technology idea and want the government to fund it you need to offer up a possible military application for the science no matter how tenuous. Your chances of getting funding increase. The GPS system started as a purely military project. The feasibility of a redundant node based distributed networking system (ie Internet) was a DARPA military project. The not so visible contributions are advances in materiel sciences, rocket sciences, computer technologies, medical advances in trauma and prosthetics , aeronautics, civilian radar networks, alternate fuel technologies. The navy is working on turning sea water into a renewable energy source for ships at sea and self-sustaining solar powered field tents. All of these technologies paid for by the military budget eventually end up in the civilian domain and as an added benefit you also end up with the most advanced and lethal military force on the planet.