[Alia]

possible terorist attacks within Japan by North Korean agents already in place

This is very worrisome. Thank you for posting on it.

[AmericanInTokyo]

Thank you for your concern. I would suspect (something like) hijacking a Japanese airliner on a domestic route, taking it over, killing the pilot and flight attendants, telling the terrified Japanese on board to sit down and shut up, and then taking the aircraft towards one of the nuclear power plants on the Western Coast, and crashing the A/L into it.

They would be yelling "Wuidehanryongdoja KimJong il dongji, Manse!" all the way it would seem--as impassioned as an "Allah Ahkbar!" Not out of the question.

I know of no air marshal system onboard Japanese aircraft and it's anybody's guess how soon the Air Self Defense Forces could scramble.

The Japanese are essentially not that good at crisis management, something big and entirely unexpected, which is very worrisome.