My intrepid Mercatus Center colleague Veronique de Rugy eloquently explains why the tragic murder of Mollie Tibbitts ought not be evidence in the case for reduced immigration into the United States . A slice:
Most credible  research  shows that immigrants, especially undocumented immigrants, commit fewer crimes, including violent crimes, than do native-born Americans. Cato Institute’s Alex Nowratesh compared  crimes rates of immigrants to those of the native born in Texas and found that in 2016, “the homicide conviction rate for native-born Americans in Texas was 3.2 per 100,000 natives while it was 1.8 per 100,000 illegal immigrants and 0.9 per 100,000 legal immigrants.”
Take, again, the example of protectionism. Not all individuals will prefer national cheeses, which implies that protectionist measures against foreign cheeses cannot be in the national interest. Protectionism cannot be in the national interest because any protectionist measure will hurt at least some individuals. For example, tariffs on foreign cheeses raise cheese prices (foreign and domestic) and hurt domestic consumers. Protectionist measures can be in the interest of a minority of nationals—or, in rare cases, in the interest of a majority—but they cannot be in the interest of all because they reduce the total volume of goods and services available for consumption in the country, as the law of comparative advantage shows.