China's "core interests" are interests so vital that China will go to war to maintain them. Tibet is a core interest. Taiwan is a core interest. Recently, China said the South China Sea is a core interest.
And this week? Well, it's the tiny Senkaku Islands:
On Wednesday, an editorial in the Communist Party-controlled Global Times newspaper said “Chinese anger of more than a century toward Japan was awakened on Tuesday” with the Japanese government’s purchase of the islands from a private Japanese owner. Beijing insists the sale is invalid, of course, because the islands, while they are physically controlled by Japan, are Chinese territory.
The Global Times, with several references to lingering bitterness over Japanese depredations during World War II, said it “appears inevitable the two sides will be overwhelmed by hatred again now that more conflicts can be expected.” ...
One phrase in the Global Times editorial on Wednesday stood out — the need for China to “protect its core interests as Sino-Japanese relations sour.”
I'm starting to think that an interest is "core" to China if China simply wants it.
What won't become a "core interest" of China the way things are going?