The Trump administration has belittled the United Nations, withdrawn from the Trans-Pacific Partnership trade agreement, jettisoned America’s commitment to the Paris climate accord, tried to renege on the nuclear deal with Iran, questioned America’s core alliances in Europe and Asia, disparaged the World Trade Organization and multicountry trade deals, and sought to shut the door on immigrants.

Mr. Xi? He has grabbed leadership of the climate-change agenda, embraced the World Trade Organization’s dispute-resolution system and increased China’s voting shares at the World Bank and International Monetary Fund. Beijing is forging ahead with a trade pact that would include the major Asian economies plus Australia and New Zealand, but not the United States. China is now one of the leading contributors to the United Nations budget and peacekeeping operations. And Mr. Xi is making a determined play to attract the world’s cutting-edge scientists and innovators to China.