It’s been proven time and again that wartime brings forth mighty technological advances which ultimately disseminate down to peaceful applications. Next on the list is one which has been part of science fiction for a long time...the railgun:

The system, when fully developed, would send an electric current along parallel rails to shoot a shell more than 200 nautical miles, or 230 miles, at seven times the speed of sound and within five meters of the target. Conventional guns, by contrast, rely on chemical powders to launch projectiles.

You know what they say: Necessity is the Mother of Invention.