The tariffs would ensnare cutting-edge smartphone and PC-related chips for Apple, AMD and Nvidia if enacted. But Trump is betting his plan will bring more chip production to the US.
www.pcmag.com
There are all sorts of ways to look at this.
1) Broadly, it is more expensive to make things in the USA than other countries, because labour costs are higher. Both due to tariffs initially and production costs later, the end cost to the customer is going to increase, i.e. inflation. This is rarely popular.
2) Chances are, all other major economic areas will do similarly. Trade will decrease, and ultimately risks a decline in quality when inferior home products end up politically favoured over better foreign. It will also breed competitors. China has a tech industry in large part because it has piggy-backed off US outsourcing. Thus instead of global behemoths like Intel, every major area will have it's own mini-Intel: and chances are at least one will end up better than Intel.
3) Who is going to work in these factories? US unemployment is very low; some of this is general churn as people move jobs, there's some voluntary economic inactivity, and let's face it, some of the unemployed are effectively unemployable. This is going to mean immigrants (politically painful), and/or a squeeze on other parts of the US labour market. The latter means job shortages in some industries and reduced capacity, probably also wage increases - which might be good, except that it's also likely to be offset by increased costs i.e. inflation.
4) It's potentially beneficial if the USA transitions back to more manufacturing. Some studies suggest that there is more economic growth available from manufacturing than services; this theory suggests the decline of manufacturing is a significant part of why economic growth has slowed since the 1980s in the West.
5) Countries will probably benefit from elements of specialisation, because it's not possible to maintain top industries in everything. For instance, if you've got a limited pool of physics graduates, you might have to consider how that talent is distributed: being great at a few things, or mediocre at a lot of things. Is this part of a properly worked-out strategy to develop industries with good future prospects that the USA can sustain?
6) Is it really a good idea to then try to also impoverish your allies and neighbours? To all intents and purposes, anything Canada makes the USA already has via trade. So the USA has it's own ~330 million people's worth of production, plus key elements of Canada's ~40 million as and when it wants. It
seems clever to steal Canada's industry, but to steal Canada's industry is essentially to give the USA 330 million people's worth of production, plus
nothing. It's actually a net
loss.