MIHAMA, Fukui Pref. — A North Korean submarine runs aground on the nuclear plant-dotted shores of Fukui Prefecture and 11 commandos armed with antitank rockets storm ashore.

Police and the Self-Defense Forces are fired on and fail to stop them, in part because of a lack of clear agreement on how Japan can defend itself. The entire nation shudders in fear that one of its nuclear installations will be attacked.

This scenario, introduced in the novel "Sensen Fukoku" ("Declaration of War") by journalist Iku Aso, is fictional, but has been drawing the attention of not only Fukui residents but military experts and lawmakers.