A Chinese naval submarine noticed in waters near the Japanese-controlled Senkaku Islands in the East China Sea last week was a nuclear-powered attack submarine, Japanese Defense Minister Itsunori Onodera said Monday. Japan’s Maritime Self-Defense Force spotted the submarine traveling in the contiguous zone east-northeast of Miyakojima, an island in Okinawa, on Wednesday afternoon. The submarine left the zone on Thursday morning, but again sailed into the zone northeast of Taisho Island in the Japanese-administered Senkaku chain later. While the Senkaku conflict is partly just another blade of grass in the meadow of Chinese expansionist disputes, it’s not an altogether unprecedented issue between both countries, writes Ben Makuch for Vice News.