evidence: On 17 June 2016, a small Indonesian Navy corvette, the KRI Imam Bonjol, encountered at least seven Chinese fishing boats and two much larger Chinese Coast Guard vessels in Indonesia’s exclusive economic zone (EEZ) near the remote Natuna Islands.[1] The Natunas are the northernmost point of this part of the Indonesian archipelago, between Borneo and the Malaysian Peninsula, stretching into the far southern end of the South China Sea. Neighbours have long acknowledged the waters north of the Natunas as part of Indonesia’s EEZ, but the Chinese Foreign Ministry has since the 1990s implied — and in 2016 for the first time openly declared — that they are "traditional Chinese fishing grounds".[2] [...] Like many other territorial disputes in the South China Sea, the origin of the contemporary dispute between China and Indonesia can be found in the infamous 1947 map drawn by Nationalist Chinese diplomats featuring a dashed line encircling much of the South China Sea. The geography of the dashed line on Chinese maps varies; however, in every version, one of the dashes intersects the northern boundary of Indonesia’s declared EEZ north of the Natunas, around 1400 kilometres from the Chinese mainland.[6] The waters in the disputed area are an important fishery and the seabed below is home to large natural gas reserves.[7]