The People’s Republic of China sent its aircraft carrier, Liaoning, through the Strait of Taiwan early this month, at least in part responding to Taiwanese President Tsai Ing-wen’s phone conversation congratulating President-elect Donald Trump.

That’s Beijing’s style: Make an unacceptable long-distance phone call, and an aircraft carrier shows up in your backyard. It is akin to proclaiming the South China Sea a Chinese province and constructing islands in international waters to house military bases; to declaring a provocative...