Just to elaborate if it is an orbital launch or ICBM test, EVEN if the trajectory passes over Japan, the Japanese cannot intercept it.
Okay...anything in the AO that CAN shoot it down?
Yep, if the Russians, Chinese, North Vietnamese or North Koreans couldn’t shoot down a fast, high-flying plane (SR-71 and other variants) then an ICBM is out of reach, at least for now.