The U.S. military today took a key step toward operationalizing a major new component of its national missile defense system, declaring the Long Range Discrimination Radar -- a hulking pair of sensors in the heart of Alaska, each six stories tall and equally wide -- fielded and ready for testing to improve defense against North Korean intercontinental ballistic missiles. The Missile Defense Agency today announced the completion of the construction and installation of the radar arrays for the LRDR at...