You said the most important part. Trump and Co believes that a car or semi factories grow overnight like mushrooms in the forest. If a CEO of a semiconductor company would decide to start building a billion dollar plant in the USA, which would take 6-8 years to built, knowing that new President from the other much different party might take over in less than 4 years, that CEO would probably endup being sued by shareholders for jeopardizing the company's bottom line.

Noone in their right mind will start building factories in USA because of temporary tariffs that all might go away with an executive order and a stroke of a pen comes January 2029.