As the venerable Tomahawk missile becomes too vulnerable for certain targets, naval observers have wondered why the Navy isn’t racing to fill the U.S. surface fleet’s 7,804 Vertical Launch System (VLS) cells with a new generation of anti-ship or fast land-attack munitions. Our wait is over. The big brains at DARPA are aiming to appropriate VLS cells for the Prompt Global Strike Mission. Meet ArcLight–the weapon that will change the way the world thinks about U.S. surface combatants: “The ArcLight program will design, build, and flight test a long range (> 2,000 nm) vehicle that carries a 100–200 lb payload(s)....