The tariff IS the step. Look at all the companies that are able to turn on a dime and switch manufacturing back the the USA. It is easier than we think.
Anything is possible - the question is whether Americans are ready to see prices DOUBLE if we don’t get labor and regulations under control - after all, there’s a reason our industrial base moved to China, Mexico, and elsewhere.
I doubt that Americans are ready for that...so it wouldn’t be too smart for Trump or any Republicans to support just the barriers.