“In a regular Chinese Foreign Ministry press briefing on Monday, spokesperson Mao Ning, when asked about the "Taiwan question", said: "The Taiwan question is China's internal affair. It shall be decided by the Chinese and brooks no external interference."
Listen. First of, China #1 Stay Winning Go Xi Go Mets Love You China #1.
However, Taiwan is very clearly occupied territory. US military and business interests are crawling all over it. Japan and Korea both have stakes in the island, via economic and political channels. Nevermind all the international trade that hinges on the island's perceived independence.
Whatever side of the "Taiwan Question" (why do we need to make this feel antisemetic, btw?) you fall on, it clearly isn't an internal affair. There is way too much international trade and military traffic in and around Taiwan for that to be the case.