Escalating tension with China, violently illustrated by renewed anti-Japanese protests in Shanghai and other big cities at the weekend, is increasing pressure on Tokyo to expand its military capabilities and back a deepening strategic alliance with the US reaching from east Asia to the Gulf.
Japan’s pacifist postwar constitution restricts its armed forces to self-defence. About 50,000 US troops in Okinawa and other bases guarantee the country’s security in return for a $5bn (¬£2.6bn) Japanese cash contribution.