AS the US Senate prepares to take up a contentious immigration bill, rhetoric about the issue has been stoked by the recent discovery of an elaborate tunnel used to move drugs and people under the US-Mexican border.
Yet regardless of the ideological background -- or nationality -- of those involved in the debate, there seems to be agreement on one basic idea: US policies to relieve immigration pressures at their source are not working. Many analysts say no such US policies to halt the inflow of illegal immigrants -- the majority of whom are Latino -- will work without help from foreign governments.
"You're not going to stop immigration because the incentives to come are all here," said Rodolfo de la Garza, a professor and immigration expert at Columbia University in New York.
"But what you can do is reduce those incentives by getting the Mexican state to address the issues that exacerbate the reasons why Mexicans leave. But the Mexican state isn't doing that."
What to do about illegal immigration -- which hit a record high in the last five years, according to one study -- has long vexed American lawmakers, who face increasing pressure from constituents to act on the issue. More than half of Americans say reducing illegal immigration should be a top foreign policy priority, according to a November Pew Research Center survey.
Recent studies estimate more than 9.0 million illegal immigrants are in the US, and a Pew Hispanic Center report from last summer found that 81 percent of the illegals are from Latin America.
At play are a number of sensitive issues: national security and fears that terrorists can penetrate US borders; the rights of migrant workers in the US; illegal immigrants taking jobs away from Americans; and the health of the US economy, components of which even immigration opponents say depend on illegal labour. This is only expected to get worse as baby boomers -- people born in the years after World War II -- get set to retire.
But analysts say the root cause of most illegal immigration -- economic disparities that push migrants north in search of better-paying jobs -- will not be cured until two things occur.
The first is that nations sending those immigrants invoke reforms to strengthen their own economies and democratic institutions. The second is that the US better coordinate its policies to give immigration as much importance as trade.
"US policy in Latin America is mainly trade policy," said Sean Garcia, a senior associate at the Latin America Working Group, a US-based coalition that focuses on American foreign policy in the region.
Trade pacts like the North American Free Trade Agreement between Canada, the US and Mexico can shake up labour markets, and Garcia notes that Latin American governments rarely offer help to those who lose jobs, especially the poorest.
"There is no support for transitioning small farmers in their domestic economies," he said. "Those small farmers are moving north to the US where there is job availability."
Jorge Santibanez, president of the Colegio de la Frontera Norte in Tijuana, Mexico, a think-tank devoted to border issues, said that economics is the obvious motivation driving people into the US But following the terrorist attacks on America in 2001, the dialogue about curbing immigration shifted to a security paradigm.
"We're now in the situation where, for Americans, security is very important. But they have a neighbour that is not able to control its own border," Santibanez said.
One example of this is the 2,400-foot (720-meter) tunnel running from a warehouse near the Tijuana airport to a warehouse across the border discovered last month. Inside authorities found two tons (1.82 metric tons) of marijuana, and note that it and 20 similar tunnels found since the Sept. 11 attacks could also allow terrorists to get into the US.
That is a valid concern, Santibanez said, but he argues the question of how to secure the border has an economic answer. Yet on neither front -- security or prosperity -- is the US getting much help from its southern neighbours.
"You don't have a partner in terms of security or in terms of development," Santibanez said. "In the long-term, it will be development as the only way to help this."
While the US may lack strong partners in Latin America in trying to curb illegal immigration, critics say the US is doing little itself to attack the issue at its root.
In December, the US House of Representatives passed a bill that allows the military to be enlisted to stop illegal immigrants at the border, requires workers to verify the legal status of employees and allows for the creation of a security fence along parts of the US-Mexican border.
All these measures do little to encourage would be immigrants to stay home, said Stephen Johnson, an analyst at the Heritage Foundation, a conservative Washington-based think-tank. He argues Latin Americans friendly to the US would be happier if Washington pushed for democratic and economic reforms in neighboring states instead of adopting stopgap measures with little impact on illegal immigration.
"Absent is a guiding strategy in foreign policy, and we haven't had one for 15 years," Johnson said.
However, Mark Krikorian, executive director of the Center for Immigration Studies, said the hands of the US government are tied when it comes to lessening immigration pressures abroad, adding that "what we can do is limit opportunities here."
Krikorian recommends enacting stricter laws for US employers who might use illegal labour, thus lessening the demand for illegal immigration. He noted that some economists argue cutting off immigration could hurt the US economy but said the impact would be softened because it would take time to implement tougher immigration laws.
"If all illegal workers disappeared tomorrow morning, the economy would be in trouble, no doubt," he said. But he added, "What would happen is the number of illegal workers would shrink over several years, allowing the economy to adjust."
The US Chamber of Commerce disagrees. Last month it produced a report outlining the labour shortage the US will face as 77 million baby boomers retire.
Thomas Donohue, president of the Chamber, said that the House-passed legislation would keep out much needed workers and instead recommended a step-by-step process in which an undocumented worker could qualify for permanent legal status.
"We have yet to secure an adequate supply of working taxpayers to run a growing economy and support an explosion of retirees," he argued.