Countries that fear they are being encircled by rivals make desperate bids to break the ring. Some of the bloodiest wars in history have been started not by rising, self-assured powers, but by countries—such as Germany in 1914 or Japan in 1941—that had peaked and begun to decline. Vladimir Putin’s recent wars in the former Soviet Union fit this same mold. Xi’s regime is tracing a fraught but familiar arc in international affairs—an exhilarating rise followed by the prospect of a hard fall.
