The United States' southern border bristles with technology and manpower designed to catch illegal immigrants and drug smugglers. Since 1986, the government has spent hundreds of billions of dollars on fences, aircraft, detention centers and agents.
But even as federal budgets shrink and illegal immigration ebbs, experts say that there's no end in sight for the growth of the border-industrial complex.
States using a federal immigration database to purge noncitizens from voter lists are starting to get results, which so far include few illegal voters.
In Florida, which was first to gain access to the database after fighting the federal government in court, an initial run of roughly 2,600 names has turned up "several" violators, according to a spokesman for Florida Secretary of State Ken Detzner.