Flying too fast for the naked eye to track, the battery-powered robot circled the Utah desert, hunting for the target it had been programmed to strike. Moments later, the drone sailed through the driver’s side window of an empty pick-up truck and exploded in a fireball.

“Good hit,” exclaimed an operator from AeroVironment, the company that produces the drone and sells it to the U.S. military.

NBC News traveled to a military testing center for exclusive access to the first-ever public demonstration of the Switchblade 300, a small, low-cost “kamikaze” drone made by AeroVironment that sources say has been used quietly for years by the U.S. military in targeted killing operations in Afghanistan, Iraq and Syria…

They can leapfrog traditional defenses to strike infantry troops anywhere on the battlefield, and they cost just $6,000 apiece compared to $150,000 for a Predator or Reaper drone. That capability could help save the lives of American troops, but it could also put them — and Americans at home — in great danger from terrorists or nation states that haven’t previously had access to such lethal and affordable technology.