Can anyone point to an historical case study where protective tariffs resulted in a better economic or social outcome? I can’t help but recall the saying: “When goods don’t cross borders, soldiers soon will.” Not that I think the United States is going to war with Canada, but the (German-dominated) EU and China are less certain.
Protective tariffs are a good idea for protecting nascent industries from essentially foreign competition. Many countries in Asia essentially locked foreign goods from certain industries during the later half of the 20th century to help build their own industries post WW 2. They ended up opening their economy once their domestic players hit a critical stage where they could compete with international players. For example, India closed off their soda, car, and other markets to spark a homegrown industry. In the 1990s they liberalized the economy and opened it to the international megacorps, but many of the domestic companies still remain in some form and there are large manufacturing plants still from that era. So it is entirely possible that protective tariffs can help for long term growth when done strategically.
However, I highly doubt any of Trump's tariff's are strategically smart.