US-China relations in frontier AI remain defined by intense strategic competition rather than coordinated restraint. The September 2026 Trump-Xi summit produced a Super Intelligence Dialogue and an incident notification channel focused on risks like autonomous agents and cyber threats, yet both sides explicitly rejected pacing development. Trump stated the US would not apply brakes and aimed to preserve its lead, while Chinese officials dismissed slowdown proposals as Cold War tactics and advanced their own speed-focused safety framework. Trader consensus at 92% for no agreement reflects these positions, the absence of any binding limits on model releases or compute, and ongoing export controls. A major shared crisis or breakthrough in November talks could still shift dynamics, though current incentives favor continued acceleration by both powers.