When Trump first started talking about tariffs this is exactly what everybody said. Unless you also introduce schemes to assist with setting up infrastructure in the US then the tariffs are not going to have the desired effect.

Nobody is going to set up a factory if there's every possibility that the tariffs will go away at some point in the next 4 years. Not unless the cost of setting up that factory is ameliorated somehow. Otherwise companies are just going to accept they're going to get fewer orders from the US for the next few years.

Especially if setting up a factory in another country means that your staff are likely to get abducted by ICE for no reason.