The two senior officials in charge of Pentagon acquisition and technology said today that they are working on several promising projects for countering drones and low-cost missiles, including everything from acoustic detection systems to directed-energy lasers and high-powered microwaves. Pentagon acquisition chief Bill LaPlante, who spoke at a panel hosted by the Center for Strategic and International Studies in Washington, said most technology to counter unmanned aerial systems needs to be at a lower price point. “The cost curve matters,”...