SHENZHEN, CHINA - MAY 1: The Chinese national flag is seen in front of stacked shipping containers bearing MSC (Mediterranean Shipping Company), Maersk, and Hamburg Süd branding at Yantian Port on May 1, 2026, in Shenzhen, Guangdong Province, China. Cheng Xin | Getty Images News | Getty Images Chinese exporters spent the past year scrambling to diversify away from the U.S., moving supply chains overseas and targeting new markets, including the Middle East, as punishing tariffs upended their business models.  Now the Iran war has heaped fresh pressure on those businesses, choking critical shipping lanes, triggering a historic energy shock, and threatening to crimp global demand for Chinese goods across the board. As U.S. President Donald Trump and his Chinese counterpart Xi Jinping prepare to talk business and politics later this week, exporters appear less concerned about tariffs and more about hostilities in the Middle East.…