China is the last people went to the two islands, after the islands were controlled by the Vietnamese feudal state for hundreds of years ago.
In 1946 taking advantage of the chaos after WW2 Japan left the two islands after surrender the Allied , Chiang's army had illegally occupied some islands.
Remember, Japan invaded the two islands in 1939 from Vietnam.
China has used force to rob the Paracel Islands from Vietnam in 1974, and robbing some of reefs in the Spratly Islands from Vietnam in 1988. Earlier Vietnam controls both the islands (Paracels and Spratlys)
Nine dotted line claim of chinese only began to appear in 1948, after Chiang Kai-shek was thought that china was a superpower, but he did not know that china only real escape from Japan due to the help of the Soviet and the U.S.
Nine-dotted line - Wikipedia, the free encyclopedia
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Chinese scholar dismisses U-shaped East Sea line as baseless
A Chinese scholar has objected to a U-shaped line that China has put in its maps to bring most of the East Sea under its sovereignty, including Vietnam’s Hoang Sa (Paracel) and Truong Sa (Spratly) Islands, calling it imaginary and having no legal foundation.
The line, also known as the “nine-dotted line,” “nine-dash line,” or “cow tongue line,” started to appear last year in American and Italian journals that cited Chinese articles with maps portraying more than 80 percent of the South China Sea, known in Vietnam as the East Sea, as belonging to China.
The concern grew after Google Maps also depicted the line several times.
But Li Ling Hua, a researcher for more than 20 years at China's National Oceanographic Data and Information Center, and the author of more than 90 reports on maritime issues and maritime laws, said at a conference June 14 that “The nine-dash line on the Nan Hai (or the East Sea) is unreal," according to a Tien Phong report Sunday.
"The line was established by our predecessors with no longitudes or latitudes, and it was not based on any laws or regulations.
“It was merely a unilateral announcement by China in 1947.”
He said the Chinese government has never officially announced the U-shaped line, but many textbooks and newspapers consider it the official sea border, making most Chinese believe it.
The Chinese government needs to clarify the legitimacy of the line, “or there will be clashes in the future” when Chinese people rely on the line to oppose any country they think is violating it.
The conference drew many scholars and saw arguments over solutions to the dispute between what the Chinese media described as “hawks” and “doves,” the latter also comprising the 66-year-old Li.
He urged the government to resolve the dispute peacefully based on international laws and regulations.
“Last month, when lecturing researchers over oceanographic studies and Chinese sea borders at Wu Han University, I also said that the real legal foundation has to be the 1982 United Nations Convention of the Sea.”
China is a member of the convention, so it should not have drawn its own borders after strong objection from the Vietnamese and Philippine governments, he said.
Countries bordering the East Sea should rely on the convention instead of their own policies to establish their 200-nautical mile exclusive economic zones and continental shelves, he said.
“Then people in every country in the area, including China, will have a 200-nautical mile area, large enough for fishing and developing marine resources.
“If neighboring countries develop economically in the future, China will also benefit. We should have a global point of view.”
The conference was organized by the Tianze Economic Research Institute and news website Sina.com to discuss national sovereignty and international regulations related to the East Sea dispute.
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