The article discusses the clash between President Trump and the Ontario government's use of Ronald Reagan's pro-free trade message in a recent advertisement. In response to the ad, Trump announced a 10% tariff increase on Canada, highlighting the stark contrast between Reagan's free-trade principles and Trump's protectionist stance.

In his article, Paul Krugman argues that Ronald Reagan was not a proponent of tariffs, contrary to claims made by Donald Trump. While Reagan imposed some tariffs for political reasons, he fundamentally championed free trade and adhered to international agreements, contrasting sharply with Trump's chaotic approach to tariff policy.