Cultural suicide used to be a popular diagnosis of why things suddenly just quit. Historians such as Oswald Spengler and Arnold Toynbee cited social cannibalism to explain why once-successful states, institutions, and cultures simply died off. Their common explanation was that the arrogance of success ensures lethal consequences. Once elites became pampered and arrogant, they feel exempt from their ancestors' respect for moral and spiritual laws like thrift, moderation, and transcendence. Take professional sports. Over the last century, professional football, basketball and baseball were racially integrated and adopted a uniform code of patriotic observance. The three leagues offered fans a...