Assessing Trump's Experiment With Protectionist Trade Policies

With President Donald Trump soon departing Washington, now is a great time to assess his protectionist trade policies. From tariffs to his hectic bullying of other governments to renegotiate trade agreements to his support for American export subsidies, the Trump years were more than infuriating on trade matters; they were destructive.

This harsh conclusion is no surprise to those of us who understand international trade. We realized from the start that the president's trade philosophy is the mercantilist one that Adam Smith debunked nearly 250 years ago.

For instance, Trump...