Border Patrol doubled in size from 1995 to 2005, reaching 11,500 agents, but many specialists and critics agree with Hellen that the buildup hasn't done much good.
``What we find pretty consistently is that the number of agents just does not seem to be related to the number of apprehensions that they make," said Linda Roberge, a senior research fellow at Transactional Records Access Clearinghouse at Syracuse University who studies immigration. ``The flood, it may go up and it may go down, but there's always more that get through than get caught."
Press officers for US Customs and Border Protection, which encompasses the Border Patrol, didn't return several calls seeking comment.
``Ultimately, I suppose if they spend enough money they can build a wall, station a Border Patrol agent every hundred yards for 2,000 miles, that might do it. But what would that achieve?" said Doug Massey, a sociologist at Princeton University's Woodrow Wilson School of Government.
Massey said Border Patrol buildups gum up a cyclical migration among mostly Mexican men who usually stay a year or two and then return home. The buildups make them stay in the United States for fear they won't be able to return, and then have their families smuggled in to join them, he said.
US Representative Silvestre Reyes, Democrat of Texas, who was chief of two Border Patrol sectors and architect of an immigrant crackdown at El Paso in 1994, said additional agents must be combined with penalties for employers who hire immigrants. ``It's all smoke and mirrors," he said. ``If the job is there, [the immigrants] will find a way to come."
A bill passed by the Senate on Thursday calls for holding employers accountable with maximum fines of $20,000 for each illegal worker hired and possible jail time for repeat offenders.
John Keeley, spokesman for the Center for Immigration Studies, wondered why there was no call to dramatically increase the number of Immigration and Customs Enforcement personnel at job sites in the interior United States.