In the early 11th century, King Canute—while at the peak of his power—set out to demonstrate to his fawning courtiers the limited power of royal edicts. After having his throne placed by the sea’s edge, he sat down and commanded the tide to stop rising. When the water began washing over his feet, he declared, “Let all men know how empty and worthless is the power of kings.” Nearly a thousand years later, facing a different force of nature—COVID-19—an entire global generation of presidents, prime ministers, governors, mayors, public health officials, scientists and citizens is being given...