Last December, Reuters reported that China had built a secret EUV lithography prototype--one of the most important pieces of equipment in Beijing’s quest for advanced semiconductor self-reliance and something barred by export controls since 2019. These machines are made up of over 100,000 components, but in my latest piece for @Diplomat_APAC, there are three big technical moats that policymakers should keep an eye on to track China’s progress. 🧵