"Won't be the case once production becomes domestic again, the original purpose of Trump's tarrifs"

Will it? Or will companies just shift to the next cheapest option in Vietnam or India?

Besides, you don't just flip a switch and have domestic production. It can take decades to build/rebuild plants and that assumes you have local suppliers for raw materials... which means they need to ramp up and find the things that they need. Ad nauseam.

Slap more tariffs on Vietnam or India? Then they too retaliate with tariffs on us and they stop buying our goods and services. (When you get down to it, DJT's tariffs are actually going to do wonders for China. Especially as the US abdicates its leadership in things like USAID.)

Either way, higher prices and in all likelihood rampant inflation for the next decade or more. Even when he gets kicked out the damage will be done.

Do people not understand basic economics? (Rhetorical question. No they don't. Hell, half the morons think China pays US tariffs and not the people who buy from there and passes the increased costs onto them.)

Negotiating with broad tariffs is like negotiating with a sledgehammer. They're a a blunt instrument in economic policy and almost always create more unintended consequences than strategic benefits.