They use outdated products, Sandia Labs and GlobalFoundries for example. Sandia labs is 350nm on 200mm wafers. The US government treats GF as a trusted foundry even though it is majority owned by a foreign government and is using outdated technology. What is the USG going to use for AI infused chips? TSMC in AZ is the only choice and that will be N-1 without a facility security clearance.
Intel is the only choice for the US Government to have secure leading edge semiconductors.
US government agencies do use old, sometimes very old, semiconductors due to long product development, manufacturing, testing, deployment, stockpiling, and lifetime support requirements. The FGM-148 Javelin anti-tank missile is a good example.
The Javelin project began in 1983, with a full scale development contract awarded in 1989 to a joint venture of Texas Instruments and Martin Marietta. The first test flight took place in 1991, and the first units were delivered to the US Army in 1996. Since then, more than 50,000 missiles of various versions have been produced. The Javelin has proven highly effective in Ukraine against Russian tanks in recent years. This long lifecycle of design, production, and support makes it impossible to use the latest and greatest semiconductors all the time.
That said, the government certainly does use cutting-edge technology when required. For example, the current top two supercomputers in the world, El Capitan at Lawrence Livermore National Laboratory and Frontier at Oak Ridge National Laboratory, are both powered by AMD EPYC server processors and Instinct GPUs. These systems are critical to US nuclear weapons research, manufacturing and deployment.
In some cases, older semiconductors simply cannot meet system requirements. For instance, the upcoming F-47 sixth generation fighter jets and the B-21 stealth bombers, like the B-2 Spirit before them, do not have vertical stabilizer and rudder. Their flight control depends on advanced computing power. Similarly, the “loyal wingman” unmanned drone concept requires F-35 and future F-47 to employ AI and supercomputing capabilities to coordinate and manage drone operations.
Another important fact is that US national security semiconductor choices are based on necessity and practicality, not ideology. Some assume the DoD, DoE, NASA, and NSA exclusively use US made chips or those produced by “Trusted Foundry” vendors. That isn’t true. TSMC manufactured chips are used in the F-35 stealth fighter and NASA’s Perseverance rover on Mars. TSMC and its Arizona fabs may never qualify as a Trusted Foundry for several reasons, but that has not and will not prevent the US defense industry and government from using TSMC made chips when required. Again, it comes down to necessity and practicality.