Commentary February 2021 reprises a red-line drama, not yet as tragedy and not as farce but definitely as a threat to world peace. The repetition tests the will of President Joe Biden’s administration to defend American security and a common-sense understanding of human freedom. On Feb. 1, communist China’s top foreign policy guru, Yang Jiechi, gave a speech to a virtual audience hosted by the National Committee on U.S.-China Relations. Yang reportedly told his audience, “The United States should stop interfering in Hong Kong, Tibet, Xinjiang”—western China where Uyghurs live—“and other issues.” Yang said these three regions are Chinese “internal affairs.” Then Yang added the most nuanced phrase: “They”—the so-called internal affairs—“constitute a red line that must not be crossed. Any trespassing would end up undermining China-U.S. relations, and the United States’ own interests.” “Red line” meaning China’s rules. Let’s deal with the nuanced reference. Please recall John Kerry derided …