Donald Trump hopes to have China help him end the war in Iran, but this goal seemed far from guaranteed as he wrapped up his two-day visit to Beijing. Xi Jinping, in turn, took the chance to warn the US over Taiwan.

China has benefited from the US's failures in Iran, but it has its own motivations to end the war

The welcoming ceremony for U.S. President Donald Trump as he arrived in Beijing for a summit with Chinese leader Xi Jinping has included a military honor guard, a military band…