However, to gain broader acceptance of an amnesty, and have immigration recede as a divisive political issue, there needs to be reason to believe that this will be the last amnesty. That from this point forward our immigration laws will be fully enforced and illegal immigration will become negligible.

The best, and probably only, way to achieve that is by an immediate, national requirement that businesses use the E-Verify system for all new hires. That is a federal program that electronically confirms legal eligibility to work in this country.

Contrary to claims by the business community, which wants to preserve an elastic supply of low-skilled workers, the current system works fine and is adequate without upgrades or improvements. The only way to defeat it is through identity theft, using the name and Social Security number of a real person.

The mandatory use of E-Verify, and a commitment by the federal government to take identity theft to defeat the system seriously, would effectively lock illegal immigrants out of the formal U.S. economy. That would reduce illegal immigration to a trickle, even without other enforcement measures commonly invoked in these discussions.