At a dinner between Donald Trump and Xi Jinping, the CEO of Nvidia is expected to take a seat — a quiet but telling sign that the semiconductor industry has become inseparable from the diplomacy of nations. The chip, once a humble piece of engineering, now sits at the center of geopolitical competition, and its makers are being drawn into the oldest of human negotiations: the conversation between powers. When technology companies join heads of state at the table, it reflects how thoroughly the tools of innovation have become instruments of statecraft.