Whether these weapons will be deployed in other, non-lethal ways or used primarily as deadly weapons in combat remains to be seen.

FORBES: Ray Guns Beam from H.G. Wells to Kickstarter and Beyond

The sonic devices could prove less deadly than so-called "non-lethal" weapons such as Tazers and pepper spray guns that have actually caused some fatalities.

NPR: Focused Sound 'Laser' for Crowd Control