I'm not American but, I think that US States have a more limited ability to actually implement trade barriers because they don't have complete legislative free

I'm not American but, I think that US States have a more limited ability to actually implement trade barriers because they don't have complete legislative freedom. Anything covered by an international treaty is off limits. Tarrifs are off limits and they generally don't have the funds to do massive subsidies. Subsidies generally are pretty hard to implement because they're 'out of pocket' trade barriers which means the funds need to be raised via tax as opposed to tarrifs which are "in to pocket." Tax breaks are "leaky pocket," but a lot easier then actually paying out. That's why treaties tend to be more lenient on subsidies. Poor countries can barely do them. Poor countries/states can't afford them. Rich countires can only really afford them for small artisanal industries with the potential to grow into big, important tech industries. Like Film production and corn farming.