Why tolerate drop-in port calls?

Regarding the Nov. 11 Kyodo article “U.S. nuke sub makes port call (in Okinawa) without prior notice“: More stupid excuses. Why doesn’t Japan intercept such a submarine as if the country was about to be attacked?

Japan should show its feelings about such incidents. Japan’s defense and security are shown as not up to par if things like this can happen. Was any alert given? Vessels from all countries should be treated with strict security in mind.

larry ejima