Somewhere in West Texas, Brian Schimpf hands me a warhead. It’s small, this explosive-carrying tungsten lump, for something built to be so destructive. This warhead is a dense three pounds and fits completely in my hand. It’s designed to be attached to Anduril’s Bolt drone, the munitions-carrying version of which is currently being built on a $23.9 million contract for the U.S. Marine Corps to blow up far-off targets. Schimpf—the cofounder and CEO of defense tech startup Anduril—looks at my warh...