On the one hand, we try to reduce the cost of transportation between England and America, or Canada and the United States, by developing faster and more efficient planes and ships, better roads and bridges, better locomotives and motor trucks. On the other hand, we offset this investment in efficient transportation by a tariff that makes it commercially even more difficult to transport goods than it was before. We make it a dollar cheaper to ship the sweaters, and then increase the tariff by two dollars to prevent the sweaters from being shipped. By reducing the freight that can be profitably carried, we reduce the value of the investment in transport efficiency.
Henry Hazlitt in Economics in One Lesson.