Laser guns, also referred to by their duller technical name "directed energy weapons," work by using high-powered light to melt through their target. In March, Lockheed released a picture of a truck engine they destroyed with their laser. Some laser targets, like landmines, are easy, because they just stay in one place. To burn through drones or incoming mortar rounds or missiles, a laser has to have a lot of power and be able to track their targets. The Navy has demonstrated a ship-borne laser against dummy boats and drones. For a battlefield system to accompany marines, they're looking at one that uses multiple trucks.