Shifting to buying more locally can work when there are local businesses that can ramp up production easily to meet demand, it doesn’t work when there is no local production that can be easily expanded, or when there aren’t enough local resources to supply local manufacturing (for example lithium for battery production)

Also, trade has been our leverage keeping China in check, we need their stuff, and they need our money, so we get along. If suddenly we say “we don’t want your stuff anymore, and we’re not giving you our money” they’re gonna turn around and sell more to India, Russia, and Europe. They’ll be fine, but we’ll both lose our leverage and toilet our economy for at least a decade while we try to recover from shooting ourselves in the leg.