Both came to power vowing to restore their nations to greatness. But America’s loud, ad-libbing president-elect, Donald J. Trump, and China’s guarded, calculating president, Xi Jinping, are glaring contrasts as politicians, and their pairing has injected new unpredictability into relations between their governments. “I could not think of two more different protagonists in the great drama of U.S.-China relations,” Evan S. Medeiros, formerly the senior director for Asian affairs at the National Security Council, said by email. “Personalities matter a lot in international relations, especially between great powers.” Read more