"Just as the Carthaginians hired mercenaries to do their fighting for them, we Americans bring in mercenaries to do our hard and humble work," wrote John Steinbeck in

. "I hope we may not be overwhelmed one day by peoples not too proud or too lazy or too soft to bend to the earth and pick up the things we eat."

Almost fifty years later the economy still cannot function without migrant labor. "Because natural population increase is unlikely to provide sufficient workers, immigration will play a critical role in sustaining the labor force growth needed to maintain overall economic growth," the Immigration Policy Center concluded in November.

The paradox is that the country’s political culture cannot function without scapegoating migrant laborers either. In December the House passed the Sensenbrenner bill, one of the most draconian pieces of anti-immigrant legislation in a generation. Meanwhile the vigilante Minutemen, no longer content to "patrol" the borders looking for illegal immigrants to "arrest," have taken to chasing day laborers at pickup sites, shouting, "This is America, not Mexico!" Every weeknight CNN airs xenophobic diatribes from Lou Dobbs posing as the friend of the common people.

No wonder two-thirds of Americans think illegal immigration is "very" or "extremely" serious and three-quarters believe not enough is being done to protect the nation’s borders, according to a

poll. Americans, it seems, love immigration. It’s just immigrants they can’t stand. The principle is central to the mythologies of personal reinvention, social meritocracy, ethnic diversity and class fluidity that lie at the core of the American dream. But the people themselves are often regarded as anathema to it.

This is not new. During the mid-1800s Irish Catholics met severe discrimination. Then there was the Chinese Exclusion Act in 1882, and during World War II, Japanese internment. Since 9/11 Muslims have been victimized for security reasons. And for the economy, there are Hispanics. So we are left despising the very people on whom we depend, and immigrants are left with the worst of all worlds–economically marginalized and socially demonized. Vulnerable to unscrupulous employers, opportunistic politicians and racist hatemongers, they work simply to exist in a place where their very existence has become an affront.

Welcome to New Orleans. For this is precisely the contradiction currently unfolding in the rebuilding of the Crescent City. Since Hurricane Katrina the city’s Hispanic population has ballooned from 3 percent to an estimated 30 percent. Every morning at Lee Circle hundreds of day laborers gather under the watchful eye of the Confederate general and wait for work. Every night hundreds sleep in a tent city in City Park, Scout Island, where one standpipe and three toilets serve about 200 people.