As President Trump prepares for his summit with Xi Jinping, Taiwan is often described as one more negotiable item in a crowded U.S.-China agenda that also includes tariffs, rare earths, Iran, fentanyl and export controls. That is a mistake.
Taiwan isn’t merely another file in the U.S.-China relationship. It has grown beyond even its traditional role as a lonely outpost for democracy and a vital test of American strategic credibility. Thanks to tech and market developments so recent that they were largely invisible during Mr. Trump’s first term, the island is now also the factory floor for U.S. leadership in artificial intelligence.