Well some how the USA managed to create wealth at a spectacular rate up until the 1960’s when trade was a tiny portion of the GDP < 5%. How did we ever manage that? You assume gloBULLism and one sided Free trade is a given good with no losers. I question your whole premise.
Well there's part of your confusion right there. Trade has always been 100% of our GDP, by definition. What you meant to say is, *foreign* trade was a tiny portion of our GDP. And foreign trade as a % of GDP is still far overshadowed by domestic trade.
For thousands of years the economic history of mankind was one long flat-line. Life sucked really bad for pretty much everybody. Then suddenly a group of countries, mostly in Western Europe and particularly the United States, took off; and a really shitty existence was replaced by relative opulence. Why?
That was Adam Smith's curiosity in 1776, when he wrote "An Inquiry into the Nature and Causes of the Wealth of Nations." He wanted to know why some nations were rich and other nations poor....I'm not going to give you an exegesis of Smith's work here, because you should read it yourself. But, spoiler alert: It was trade!
Just imagine a world without trade. How well would you, or any of the rest of us, get along? Grow your own food, make your own clothes, build your own house....What about a car? Where to get the parts? Maybe just a wagon and a horse. But where to get a horse, unless you can trade something for it. Trade? What's that?