> I don't expect that these tariffs will last for long - when he or his cronies notice they are destroying the economy, there will look for a quick exit
The new tariffs could be cancelled tomorrow, but the knock-on effects will take months, if not years to settle. Look at how long it took for the disruption from Coronavirus to settle; arguably, things are still settling, some four years later.
Then too, the american businesses which these tariffs are meant to be helping are pretty much screwed every which way.
In the short term, they're going to have significantly higher production costs. Which means that their revenue and/or profit margins are going to drop.
So, they're going to have to cut costs (aka: fire employees) while deciding what to do next.
If they think that the tariffs are going to be short-term, they can maybe try to hang on as-is. But that'll leave them exposed to the risk that some other company may be able to spin up local infrastructure and undercut their prices.
On the other hand, if they think the tariffs are going to be around for a long time, they can invest in their own local infrastructure. However, this generally carries a significant upfront cost, and takes time to get up to speed; Tesla's gigafactories allegedly take around 18 months to build, plus another 15 months to reach full production capacity.
(Equally, from a wider economic perspective: any new infrastructure will generally attempt to minimise costs through automation, so there's not going to be any significant boom in employment; a company may hire just one person to do the job that (pre-offshoring) ten people previously did. And that's assuming you can find skilled staff without also investing heavily in training and education![*])
Worse, even if you do manage to secure funding, build your infrastructure and find people to staff it, your production costs are probably still going to be higher than those of your offshore rivals. So you'll struggle to export your product, especially if the countries you're trying to sell to have imposed equivalent tariffs to those currently being applied by the USA.
And if the US tariffs are dropped at some point in the future, you'll be completely shafted: your products will be too expensive to export, while you're also simultaneously being undercut by imports.
Any which way you look at things, it's likely to be a bumpy ride!
[*] To quote https://www.trade.gov/sites/default/files/2022-07/2019ReinvestmentReport.pdf:
[For Carey Manufacturing] The costs of reshoring, particularly the costs associated with new capital equipment, were high [and] may require five to six years to see a return on investment.
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Edgewell [...] created an estimated 160 jobs in Dover (fewer than the number of jobs in [the offshore factory] due to efficiencies gained)
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Edgewell continues to have difficulty finding mechanics and machine operators in the United States. At the Dover facility, Edgewell only hired one engineer from the local area, and several jobs remain unfilled after three and a half years.
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QED noted that it has had difficulty finding workers with the appropriate level of technical training as well as soft skills. The company has noticed this labor challenge in the overall U.S. labor market as well.