There used to be lots of chipmakers in the United States.
Used to? (That's AMD's spin off).
It appears the US is still a major player in the CPU market. China's current huge advantage isn't the ability to make top-end chips. Its advantage is in rock bottom assembly prices, combined with the flexibility to make almost overnight changes to manufacturing processes. That flexibility is partly due to their reliance on cheap human labor that might even be on call 24 hours a day. If you try to change a process in a mechanized/automated plant, it takes time and very possibly some retooling. To change a process in a factory relying on cheap labor, it takes a few hours of classroom time and a trainer.
That said, the US has some major manufacturing problems. The US is no longer capable of making what they used to make. It seems that some expertise is gained/maintained by being close to or involved in the end process, and if you rely on other people to do it all, you lose the ability. I'm not wading into the rest very deeply, but I will admit that there are a lot of reasons that it costs more to manufacture things in the US that don't involve labor costs or the environment.