One of the hottest items in bookstores across China is a map for a place that is closed to visitors, home only to animals such as goats and crabs, and the reason China’s relations with Japan are at their lowest point in years.

China calls them the Diaoyus; Japan, the Senkakus. The new map shows a satellite image of a kidney-shaped main island with splotches of green, and a list of 70 affiliated “islands” that are really half-submerged rocks.

China hastily published the map to help maintain public outrage over the Japanese government’s purchase of some of the islands from their private Japanese owners. Beijing also has engaged in another type of mapmaking that may end up escalating the conflict.

It has drawn new territorial markers, or baselines, around the islands, and submitted them to the United Nations. That could lead to a more serious attempt to claim the islands, and broad swaths of valuable ocean around them.

“The status quo has been broken in the last month by Japan’s purchase and China’s publishing of the baselines,” said Stephanie Kleine-Ahlbrandt of the International Crisis Group. She said friction is likely to reach its worst level since the 1980s when China and Japan tacitly agreed to set aside the dispute in pursuit of better overall relations.

More than lines on paper are at stake. By submitting the baselines to the U.N., China is spelling out its claim to the waters, the fish in them and the oil, gas and other minerals beneath them. Up until now, China has sought to jointly exploit resources with Japan through negotiation.

Japan says it bought to islands to maintain stability, noting that the nationalist governor of Tokyo had been pushing a more radical plan to not only buy the islands but develop them. China, however, was outraged, and considered Japan’s move a violation of their earlier agreements.

The dispute has brought nationalism and patriotism to the fore, and sparked sometimes violent protests in China targeting Japanese businesses, restaurants and cars. A Chinese man driving a Toyota Corolla was beaten unconscious by a mob in the tourist city of Xi’an and left partially paralyzed, according to state media. Chinese and Japanese coast guard vessels have been facing off in the contested waters.

The dispute is testing perhaps the most important economic relationship in Asia, between the world’s second- and third-largest economies.

Japan has claimed the islands since 1895. The U.S. took jurisdiction after World War II and turned them over to Japan in 1972. China says they have been part of its territory since ancient times, and that it opposed and never acknowledged the deal between Japan and the United States. Taiwan also claims them.

The islands make a strange setting for a potential conflict zone. The largest is less than 4 square kilometers (1.5 square miles). It is home to a growing population of goats – the offspring of a pair brought there by right-wing Japanese activists in 1977 – as well as moles, crabs, Okinawan ants, albatross and lizards, and plants including azalea.

The islands themselves are remote, “intrinsically worthless features” that were largely forgotten for decades, said Clive Schofield of the Australian National Centre for Ocean Resources and Security at the University of Wollongong.

2012 Bennett, Coleman & Co