Our arguments over a wall at the U.S.-Mexico border encapsulate much of what’s wrong with American politics. The wall has become a much larger issue than it deserves to be, and the parties have been unable to make a deal over it that ought to be easy to make.

The debate is overwrought on both sides. It was a mistake for immigration hawks to become as fixated as they have on building a wall on the southern border. Even if it is completely successful in stopping illegal border-crossings, it won’t stop people from coming here legally and then overstaying their visas. Estimates of the fraction of illegal immigrants who get here that way range from two-fifths to two-thirds.

Requiring employers to use E-Verify to make sure that all new hires are legally allowed to work in the U.S., on the other hand, would reduce the incentive for both illegal border crossings and illegal overstays. The rationale for a wall would shrink.