Homeland security and immigration and customs enforcement (Ice) agents claimed the raids were prompted by an inquiry into identity theft. But less than a quarter were charged with using false security cards - the rest were deported. Ice's assistant secretary, Julie Myers, said Operation Wagon Train had dealt a major blow in the "war against illegal immigration".
The border is no longer just a physical space that separates the US from Mexico. It has become a political space that reproduces itself throughout the country. While immigration officials are mounting raids, local councils across the country are passing ordinances preventing undocumented immigrants from settling. Last month, voters in the Dallas suburb of Farmers Branch voted 68% to 32% to ban landlords from renting to illegal immigrants. Nine months ago, Hazelton in Pennsylvania went further, also banning the hiring of undocumented workers and declaring English the town's official language. The legality of both decisions is dubious and being challenged. But the political momentum they represent is unmistakable. More than 100 municipalities around the country are considering or have passed similar laws.
Not all are hostile. City officials in New Haven, Connecticut, approved a plan last week to offer undocumented immigrants identification cards so they could open bank accounts and use other services. But most are. Immigration-related laws currently sit before all 50 state legislatures, with most aimed at restricting the rights of undocumented workers. The Americans for Legal Immigration Political Action Committee, an anti-immigrant group, has launched Operation City Walls. "We are prepared to take this country back from the grassroots up," says Alipac's president, William Gheen. "We are ready to re-establish citizen control."
While the physical border marks a geographically fixed, if historically fluid, area (160 years ago Colorado was part of Mexico), the political border is more arbitrary. It divides families and terrorises communities, and cannot be effectively enforced without ethnic profiling. "I can tell an illegal just by looking at them," a Minuteman, from the anti-immigration vigilante group, once told me in New Mexico. "It's like wild dog versus tame dog. They just don't have the same kind of look."
The strictures and structures of this omnipresent border owe more to economic expediency and political opportunism than either law or order.
"They took the workers out in cuffs," says Roberto Cardova, a Chicano activist and member of Latinos Unidos. "Why didn't they take the bosses? Why don't they raid the expensive ski resorts of Aspen or Vail? Why don't they raid Las Vegas? Those places would fall apart without undocumented workers, but then rich people would complain."
Marginalising immigrant communities is not just the effect of the political border. It is its purpose. With 12 million undocumented workers in the country, picking them off 1,000 at a time is no solution - particularly when some of the deported Greeley workers were back within a week. But as a sop to anti-immigrant campaigners it can make life less bearable for the migrant labourers already here. "We don't need to deport them," said Randy Graf, a Republican candidate for an Arizona border district, before congressional elections last year. "All we have to do is enforce our employment laws and pretty soon they won't be able to get a job and will self-deport."
There are two key problems with this plan. First, it ignores how integral illegal immigration is to the US economy. According to a recent paper by Gordon Hanson, of the University of California, San Diego, the undocumented comprise a quarter of farmworkers, 17% of cleaners and 14% of construction workers. After Colorado passed tougher anti-immigrant laws last year, migrant labourers fled and crops rotted. In March, the state's department of corrections proposed getting prisoners to pick melons, onions and peppers at 60 cents an hour.
Second, this nativist populism has proved not quite as popular among the natives as its advocates imagined. They are vocal and committed but have struggled to give that voice electoral expression. Graf, a Minuteman, stood in a seat where Republicans won 60% of the vote in 2004. He lost in November with just 42%, primarily because his anti-immigration views were regarded as too extreme. The likes of Graf cannot win, but nor can they be ignored.
The result has been legislative paralysis, which saw yet another immigration bill stall in the Senate last week. The bill would have fortified the border, provided a costly pathway to citizenship for the undocumented workers already in the US, and shifted the emphasis for future migration from family ties to professional qualifications. It would have also seen the introduction of "guest worker" visas, allowing some immigrants to work in the US for two years and then return home.
Bush backed it, as did big business. Democrats and progressives mostly supported it with reservations. The public were ambivalent - according to a Pew poll last week a third backed it while 41% were opposed. But Republicans hated it. Two senators from South Carolina and Georgia were booed at their respective Republican party conventions two weeks ago for having favoured it.
But immigration does not just present a challenge for the right. Had the bill succeeded it would have provided a blueprint for Latin America to assist and indulge America's addiction to cheap labour. Migrants are generally believed to depress low-skilled American wages by around 5%. The state should not be teaming up with big business to keep it that way or, worse still, depress them further. The solution is not in vindictive local law enforcement but international, and particularly regional, development.
Regional agreements such as Nafta and Cafta have liberated capital while local politicians criminalise labour, and immigration laws seek to imprison the poor in the poverty of the developing world. There are more successful blueprints available. Nafta should follow the EU's example of combining the free movement of labour with social cohesion funds to develop poor areas, whether in Detroit or Guadalajara. By promoting better labour laws and a regional minimum wage Nafta could provide an acceptable floor for wages and living standards rather than a ceiling that gets lower as the desperate barter their value down to subsistence.
Such a plan is no more fanciful than politicians erecting legislative walls to keep the rest of the continent out of their hamlets. With 53% of children in the school district Hispanic, Greeley's future is Latino. And Latinos are already running the show. Not long after the Ice raid, Swift was bought by Brazilians.