China controls the upstream production chemistry for many of the most widely used generic drugs in the United States, leaving few backup suppliers if that access were disrupted, according to a recent report by former U.S. government officials. The vulnerability is drawing fresh attention as Chinese leader Xi Jinping is expected to travel to Washington, D.C. for a state visit on September 24, the first trip by a Chinese leader to the U.S. capital in more than a decade.

American and Chinese officials have spent recent weeks preparing for the visit, and artificial intelligence and trade friction are expected to dominate the agenda. Still, pharmaceutical dependence carries the same kind of coercive potential Beijing has shown in other sectors, and it touches medicines that tens of millions of Americans take every week.

Beijing has used that kind of leverage before. It restricted rare-earth exports to Japan during a 2010 territorial dispute, imposed trade barriers on Australian barley and wine after Canberra called for a COVID-19 origins inquiry, and curtailed trade with Lithuania after Vilnius opened a Taiwanese representative office. In none of those cases did Chinese officials announce the move or explain the reasoning beforehand.