Hard-learned experience demonstrates that free trade builds prosperity; when goods cross borders to link willing sellers with eager buyers, everybody benefits. Unfortunately, in his second term in office, U.S. President Donald Trump is doubling down on the protectionism of his first term and of his successor and predecessor, President Joe Biden. Using the vast — really, excessive — powers of the presidency, Trump is imposing enormous costs on America’s trade partners. But he’s also inflicting economic pain on the Americans he claims to be helping.