China defends their aggressive stance on the Senkakus by appealing to history despite the long gap between China's claims and actual ownership. Be careful if China is establishing a Han version of the Brezhnev Doctrine.
China continues to lean forward in their newly resurrected dispute with Japan over islands north of Taiwan. Peking's justification should send shudders through the region:
China is continuing to send its vessels into waters around Japanese-held islands. Beijing says the territory has been Chinese since “ancient times.”
That's an interesting justification. What was once theirs will be theirs again?
So who needs to be worried about future Chinese claims based on the Old Han Doctrine?
There's Taiwan, of course. And most of the South China Sea.
But recall that much of the Korean peninsula was once owned by China.
Huge chunks of Russia's Far East were taken from China.
Mongolia was once within China's borders.
I think bits of Central Asia beyond their current border was once Chinese, including a small bit of Afghanistan.
Parts of India.
A good stretch of Vietnam stretching south into former South Vietnam.
Bits of Laos.
That's off the top of my head. Would China claim lands where their sailors stopped for tribute in the 16th century around the Indian Ocean shores of Africa (and into the Atlantic) and the Persian Gulf?
You never can tell what will become a Core Interest of China.