… is from page 90 of Pierre Lemieux’s excellent 2018 monograph, What’s Wrong With Protectionism? (footnote deleted):
Typically, a producer’s “unfair” advantage simply derives from comparative advantage. Sometimes comparative advantage is man-made or “artificial,” which does not make it less of an actual comparative advantage. Government subsidies are a sort of artificial comparative advantage; there are good reasons to oppose subsidies, but these do not constitute an argument against free trade. Foreign subsidies are not deemed unfair by the consumers (or businesses) who benefit from lower prices. One wonders why people who appreciate subsidies from their own government would reject them when they come from foreign taxpayers.