Drone warfare. Believed to be the future of US military policy. But another battle is taking place within the United States, one centering on non-weaponized drones within its skies. Experts gathered at the National Press Club to discuss these unmanned aerial vehicles. Increasingly sophisticated technologies have raised many concerns with regard to civil liberties. Experts estimate that up to 30,000 new drones may be roaming US skies within the next decade.