Importing might be banned until the US loses access to its main source of GPU manufacturing. And what are the US going to do about it? Defend Taiwan? With missiles made with components and materials processed where, pray tell?

The US does need to start protecting its manufacturing again, but it’d be lucky to start at a level as high as high end semiconductors. That’d be like a stroke victim trying to run before they re-learn to walk.

As others have pointed out, this means less services, more manufacturing, less consumption, a probably a lower standard of living. But with the business as usual alternative looking a lot like business as usual in the western Roman Empire circa 450 CE, taking a hit to your standard of living while investing in a future which you still have the slightest control over, maybe feels like a decent trade.