Casey Mulligan reminds National Review Online readers that fellow high-profile economist Paul Krugman is wrong about many of the issues that attract his attention.

Professor Paul Krugman “has a good understanding of the essentials of international trade (the basis for his Nobel Prize Award) and explains them well,” I wrote in December in my new book about President Trump and his economic team. But I added that Krugman “is wrong about most [other] economic subjects . . . [and] helpful for predicting mistakes that would be made by the President’s opponents.” …

… Throughout the summer of 2020, Professor Krugman opined on the consequences of renewing in-person schooling. … [H]is amateur and partisan theory of disease trumped that assessment. He advised his five million followers that reopening school this fall would “be a complete disaster” that “would kill thousands” as it “disastrously reinforc[ed] the pandemic.” …

… Many schools did in fact dare to open. … Using a larger dataset, Brown University professor Emily Oster found that “schools aren’t super-spreaders . . . fears from the summer appear to have been overblown.” Krugman had no business stoking those fears with an improbable scenario from outside his expertise, when he knew that the human-capital costs to children of e-learning were enormous and guaranteed.

This spring Congress hastily prepared a pandemic assistance package that ultimately proved to pay the unemployed almost $1,000 per week (primarily a special $600 “bonus”), which was more than most of the beneficiaries were earning before they were laid off. …

… Professor Krugman had, to put it charitably, a unique perspective. “I’ve been doing the math, and it’s terrifying . . . the end of benefits will push down overall consumer spending . . . more than 4 percent,” he wrote in early August. Furthermore, he insisted that drop would be followed by “a substantial ‘multiplier’ effect, as spending cuts lead to falling incomes, leading to further spending cuts.”

Although not mentioned to his readers, Krugman’s conclusion is the opposite of a decades-long consensus in our profession.