The Smoot-Hawley Tariff increased tariff rates on over 800 items with an average rate of 59.1 percent, as high as it had ever been. Twelve countries immediately retaliated by placing high tariffs on American imports into their own countries, spawning an international trade war. By March of 1933 international trade by the seventy-five most active trading countries had shrunk from $3 billion/month to less than $.5 billion/month, an 83 percent reduction. This meltdown of world trade imploded the international division of labor and greatly exacerbated the Great Depression.
Think about all this the next time you hear President Trump wax eloquently and lovingly about protectionist tariffs and threaten 200 percent tariffs on country after country, oblivious to the societal train wrecks that protectionist tariffs have caused throughout American history.
Yes, free trade works well if all of the countries engage in it. When some of the countries engage in raw, hard mercantilism, being a free trader has some problems if your own people cannot afford to buy the foreign goods. Yes, mercantilism hurts all involved in it, too.