But Mr. Krugman really shoulda put more emphasis on another couple facts: That only "convenient" facts matter to Trump's political base. And that Washington decision makers who care about facts are going the way of the 8-track tape.
Canada's advertisement aired during one of the World Series games, after Trump's initial tweet. As others here have commented, Reagan's position was more nuanced than "tariffs bad", which is how the ad portrays it. Krugman himself admits this in his own article.
Then Krugman goes on the usual ad hominem attack against Donald Trump, because he just admitted that Reagan was in favor of using tariffs to settle political disputes, particularly in response to countries leveling tariffs against the U.S.
Which, mind you, is exactly what Donald Trump says he is doing, raising tariffs on Canada in response to several long-standing tariffs they have had on the importation of U.S. goods. Krugman doesn't dispute this. He cleverly doesn't bring it up at all and instead calls Trump a petulant child levying tariffs for his own political purposes.
Forgive me if I can't take Krugman or anyone else parroting Krugman seriously when he hasn't been able to make a soundly reasoned argument in decades. These low-on-facts high-on-rhetoric articles are empowering Trump.