The Pentagon is eyeing a next-generation Ballistic Missile Defense System that adds directed-energy weapons to its arsenal, including a potential high-powered airborne laser to defeat long-range adversary rockets during the boost phase of flight, according to a senior military official. In the next decade and beyond, Missile Defense Agency Director Vice Adm. Jon Hill predicted the $200 billion system of integrated sensors, command and control tools and effectors that collectively make up the Ballistic Missile Defense System the Pentagon is...