These are all matters of incremental trade-offs to find an optimal amount and kind of safety, in a world where being categorically safe is as impossible achieving 100 percent clean air or clean water. Incremental trade-offs are made all the time in individual market transactions, but it can be politically suicidal to oppose demands for more clean air, clean water or automobile safety. Therefore saying that the government can improve over the results of individual transactions in a free market is not the same as saying that it will in fact do so. Among the greatest external costs imposed in a society can be those imposed politically by legislators and officials who pay no costs whatever, while imposing billions of dollars in costs on others, in order to respond to political pressures from advocates of particular interests or ideologies.
Throw in your best guess! No cost to play and a grand prize awaits the winner. Hint. Extracted from a 2007 book where on the rear jacket cover the WSJ says, “Clear and concise…Among economists of the past thirty years, (your guess here) stands very proud indeed.”