Exclusive: a Harris poll raises questions about the popularity of one of Trump’s key economic policy platformsUS politics – live updatesTwo-thirds of Americans think Donald Trump’s tariff plans will only add to rising costs if implemented, and many are planning purchases ahead of his inauguration anticipating higher prices, according to a Harris poll conducted exclusively for the Guardian.Trump declared on Monday evening that he would impose 25% tariffs on all goods from Canada and Mexico, and an additional 10% on China, if they did not stop what he claimed was illegal immigration and fentanyl smuggling. Continue reading...