evidence: Vice President Kamala Harris, in making her case, said that the tariff plans Donald Trump is proposing will hurt the middle class. Here's what she said specifically: "he intends to enact what in effect is a national sales tax, call it a Trump tax, that would raise prices on middle class families by almost $4,000 a year." Now the estimates vary, but how do you respond to that charge that Trump's tariffs would hurt the middle class? [...] Second, the cost figures Harris was referring to are based on the 10-20% universal baseline tariffs proposed by Trump. The $4,000 figure could be derived from the following studies: "The Center for American Progress released a report concluding that costs for American families would increase by $3,900 per year if Trump were to impose a blanket 20 percent tariff on imports, while the National Taxpayers Union estimated in February that Trump’s original suggestion of a 10 percent tariff would cost households $3,942 per year." In his response, Vance focused mainly on China, which ignores the point that Harris was making about the universal tariffs, and therefore his comments don't add much to the discussion of Trump's proposal to impose these tariffs. [...] And as a general point, I think people would be shocked at the price rises that would result from Trump's recent tariff proposals, and that would put an end to the debate about tariffs. But I hope we don't have to actually experience this to learn that lesson.