Trump heads to Beijing hoping personal ties with Xi can ease tensions but Iran, tariffs, Taiwan and China’s expanding global influence have complicated prospects for meaningful breakthroughs at the summit… Beijing’s deep economic relationship with Tehran, especially its dependence on Iranian oil — has placed China in a delicate position as Washington seeks broader regional support… Trump’s first presidency was dominated by tariff battles with China, many of which reshaped global trade flows even after some measures were later struck down in US courts… While a temporary trade truce last year reduced some pressure, the underlying disputes remain unresolved... The...