When I was 8 years old, my father explained to me the secret to American prosperity.

Immigrants come to the United States and take menial jobs so that their children have a chance at a better future, he told me. While the jobs they take are below their intrinsic capabilities, they’re focused on giving their children a better life, not personal job satisfaction. Second-generation children, seeing how hard their parents work to give them an opportunity, in turn work hard at school, where, he noted, they often focus on mathematics and science in pursuit of the economic returns promised by careers in engineering and medicine. Third-generation kids figure the economic return on effort expended is better for business and legal professionals and pursue those professions instead of technical ones.  By the fourth generation, any immigration-related incentives to work hard are largely nonexistent.

It was a gross generalization used to explain to a child the importance of immigration, but one that I have since found to be generally accurate.

On this 233rd celebration of U.