In late September 2026, President Trump and Chinese President Xi Jinping convened for a state visit in Washington as the United Nations General Assembly wrestled openly with the governance of artificial intelligence — a technology that has quietly become the defining arena of great-power rivalry. The meeting carried the weight of a civilization-level question: can two nations locked in strategic competition find the discipline to set shared guardrails on a force neither fully controls? Harvard's Graham Allison, a lifelong student of how empires navigate dangerous transitions, offered the inter