Semicon industry is much more tightly knit together than what you suggest.You realize if Europe tries what you suggest they loose right? Social media is all American owned, most media is American owned, technology is American owned. Remember Trump promised to reciprocate any tariffs placed on America, those cheap Ryzen 5 chips or i3 could cost you $1000 USD for what was $150 USD, also American companies may get the greenlight from Washington to ignore all of your laws, and there would be nothing you could do about it.
For example, ASML, which Intel absolutely requires for their catch-up, is from the Netherlands, but is used in Taiwan or US or wherever advanced chips are made. Inside an ASML machine there are hundreds of parts from other countries, in Europe, US, Asia, ... Same holds for every other tool used to make chips.
There is a reason the EU is the biggest trade-block worldwide, even though it is not the big tech companies you refer to but mostly many smaller companies, and that most US companies buy lots of parts from EU companies (and vice versa). In the current just-in-time, finely knitted together global economy it is therefore not that simple to even predict what tariffs will really accomplish, just a gamble. Personally I think it is a gamble where US and EU will both lose in the end, and Russia and China will gain.
I'm not taking sides here, just pointing out the real complexities and fractal nature (and, as we know, the chaotic nature of fractals, by their very definition, makes them unpredictable).