Those who favor government intervention in the economy often depict those who prefer free competition as Adam Smith's pro-business apologists. Anyone who has driven in most big cities might feel there's an unmet need for more parking spaces. Doing so would mean fewer hospitals, fire stations and other buildings. The point Sowell constantly makes is that scarcity is mankind's perennial state of affairs. That being the case, in order to have more of one thing necessarily means having less of another.
Tradeoffs become a fact of life.