China's Export Blacklist Exposes Limits of Unilateral AI Controls

China's targeting of 56 US companies in retaliation for semiconductor export restrictions shows that supply chain restrictions trigger escalation, not compliance. When one nation cuts off access to critical inputs, competitors build alternatives and domestic capacity instead. The result is a fragmented global AI stack, where companies must choose location over technology. Frontier AI development is already shifting as a result, and access to the global AI economy is narrowing by jurisdiction.