Commentary Wars often arise from uncertainty. When strong countries appear weak, truly weaker ones take risks they otherwise would not. Sloppy braggadocio and serial promises of restraint can trigger wars, too. Empty tough talk can needlessly egg on aggressors. But mouthing utopian bromides convinces bullies that their targets are too sophisticated to counter aggression. Sometimes announcing “a new peace process” without any ability to bring either novel concessions or pressures only raises false hopes—and furor. Every new American president is tested to determine whether the United States can still protect friends such as Europe, Japan, South Korea, and Israel. And will the new commander in chief deter U.S. enemies Iran and North Korea—and keep China and Russia from absorbing their neighbors? Joe Biden, and those around him, seem determined to upset the peace they inherited. Soon after Donald Trump left office, Vladimir Putin began massing troops on the Ukrainian border …