When the leaders of the world's two largest economies sat down in September 2026, the old grammar of great-power rivalry had acquired a new vocabulary. Artificial intelligence now commands the same diplomatic weight as trade and military posture, signaling that both Washington and Beijing have concluded that whoever leads in AI leads in everything that follows. The conversation between Trump and Xi is less a negotiation than a mutual acknowledgment that the contest for technological supremacy has become inseparable from the contest for the future itself.