Economist Herbert Stein’s old adage—”If something cannot go on forever, it will stop”—still holds. Take illegal immigration. There are currently somewhere from 11 million to 15 million immigrants living in the United States without legal authorization. Last month, nearly 100,000 people were apprehended or turned away while trying to illegally cross the southern border. Some experts suggest that at least that number made it across without arrest. 

The U.S.-Mexican border is essentially wide open. Why? Because there is a general expectation in Mexico and Latin America that American immigration law is unenforced. Or it is so bizarre that simple illegal entry almost always ensures temporary legal residence, pending an asylum hearing.

Hoover Institution fellow David Henderson discusses how “Trumponomics” is playing out in the economy, and analyzes whether the growth we have seen under Trump’s presidency is sustainable.

Immigration is a contentious topic. To complicate it further, immigration should often be broken down into several distinct topics. It can mean legal or illegal immigration, it can mean permanent or temporary visas, and it can mean preventing future flows or managing existing stocks.