The absence of Chinese President Xi Jinping and Russian President Vladimir Putin at the G20 heads of government summit in New Delhi brings clarity to the future shape of geopolitical power. Three poles are visible, though in overlapping parabolic axes. The first axis is the United States-led coalition of democracies. The second is the China-Russia axis of autocracies. The third pole is the amorphous Global South led by India and other neutral powers. The catch in this tripolar world is that several countries have divided loyalties. The newly expanded BRICS, for example, has traditional US allies like Saudi Arabia and...