Who gets to decide which supply chains deserve the protection of nationalism? Sounds to me like a recipe for out of control rent seeking, as every widget maker and its upstream suppliers descend on Washington for their handout.
Emperor Jaw would not have a which. I would start with a baseline 200% import tariff on everything but raw materials. Strategic exemptions with UK, Canada and Mexico to start, eventually expanded to include Central and South America. I can't think of anything we get from the Aussies but I would toss them in with the UK too, just to keep them from being dependent on the EU and China.
I would have fairly lofty goals.
Return the manufacturing industry to the US and increase geostrategic security by establishing an updated, US dominated, version of the Iron Curtain that the Soviets controlled. And devestate China's manufacturing industry, obviously.
Both American continents can provide every raw material needed, some jobs would return to the US and others could strengthen Central and South America.
The environment benefiting from transporting billions of tons of cargo fewer around the world, removing a massive amount of manufacturing from countries in Asia with the lowest environmental standards, and from a stronger bargaining position to demand better stewardship of the rainforests.
Hopefully the combination of stronger economies in, and closer ties with, Latin America, along with a stronger middle class in the US, would lead to greater portability to and from the US. American money going south to poorer countries where it's needed. Motivated and culturally conservative immigrants going north from poorer and overpopulated countries to where they're needed.
Oh, I almost forgot about returning top tax levels to 91%, just like the last time we realized we were in a Cold War. If it worked through the golden era of the 50s and 60s it should work again.
That's the outline anyway.