Artificial intelligence is booming. Tools like ChatGPT are getting more capable at an impressive rate as companies race to plug them into new areas of the economy. But the burgeoning demand for AI computing power faces a big constraint: the graphics processing units, or GPUs, needed to train and deploy these models. These specialized, costly GPUs are almost entirely made by one company — Nvidia — at one manufacturer in Taiwan, according to Chris Miller, a professor of history at Tufts University and author of “Chip War: The Fight for the World’s Most Critical Technology.”