The Army’s top missile defense commander voiced concern over a newly disclosed delay to the Pentagon’s Next Generation Interceptor, warning that the three-year slip leaves the U.S. homeland exposed to advancing North Korean missile threats longer than previously anticipated. “Any delay to the system is obviously concerning,” said Lt. Gen. Sean Gainey, commanding general of U.S. Army Space and Missile Defense Command (SMDC), during a May 2 briefing with reporters at the Pentagon. “I’m concerned.” Gainey’s remarks follow testimony earlier...