… is from page 486 of the 5th edition (2015) of Thomas Sowell’s Basic Economics :
Despite offsetting economic gains [from free trade] that typically far outweigh the losses, politically it is almost inevitable that there will be loud calls for government protection from foreign competition through various restrictions against imports. Many of the most long-lived fallacies in economics have grown out of attempts to justify these international trade restrictions. Although Adam Smith refuted most of these fallacies more than two centuries ago, as far as economists are concerned, such fallacies remain politically alive and potent today.
Protectionism remains a threat because the enormous rents captured by protected domestic producers are easy to see and easy to be mis-portrayed – today by the likes of Pat Buchanan, Lindsey Graham, William Greider, Peter Morici, and others who are poorly informed economically – as benefits to society rather than as the costs that they are.