High-level communication between the U.S. and China is key. Absent that communication, mistrust and miscalculation might see this increasingly hostile relationship inadvertently slip into war. But beyond limited improvements to communication, the prospect of a U.S.-China detente is nearly nonexistent. President Joe Biden hinted at such a detente last weekend, observing that U.S.-China tensions would "begin to thaw very shortly." Biden was likely referring to high-level meetings. National security adviser Jake Sullivan recently met with the Chinese Communist Party's Central Foreign Affairs Commission director, Wang Yi. In Washington this week, Commerce Secretary Gina Raimondo will meet with her Chinese counterpart,...