In the ongoing border-immigration debate, American Populists describe the issue of broken borders in dire, almost apocalyptic terms. There is a common front in our illegal-alien crisis, the war on drugs and the global war on terror, CNNs Lou Dobbs argues, throwing everything but the proverbial kitchen sink into the mix. That front line is easily defined as our nations borders, airports and seaports. They demand an air-tight border with Mexico. They seek law enforcement so punitive that all the 12 million undocumented immigrants now residing in the U.S. would have no choice but to leave. If they win the border battle, the United States could lose Mexico.

In their fervor to seal the border, the Populists ignore geopolitics. Yet, geopolitics is the biggest issue of all. The outcome of the border-immigration debate could become the tipping point that turns Mexico away from the United States.

Over the past decade, Latin America has witnessed the election of a growing number of left-of-center governments. That trend has quickened in recent years. Three factors have driven this trend. In an article published in the May/June 2006 issue of Foreign Affairs, Jorge Castaeda, former Mexican Foreign Minister, argued that the fall of the Soviet Union removed the geopolitical stigma from Latin Americas left, Latin Americas extreme inequality creates a hospitable environment for leftist governance, and the spread of democratization made it possible for leftist governments to gain power through the electoral process.

The populist variant of the left-of-center governments are the most troublesome for the United States and its critical interests in Latin America. Castaeda explains, These populists are...always authoritarian in one fashion or another, and much more interested in policy as an instrument for attaining and conserving power than in power as a tool for making policy. Venezuelas President Hugo Chvez is the most recognizable face of Latin Americas radical populists.

Mexicos historic experience and present circumstances suggest that one cannot altogether discount the rise of such a leader in Mexico. First, according to the CIAs World Factbook, 40% of Mexicos population lives below the poverty line. In Latin America, the average is 43%. Second, Mexico has experienced authoritarian ruleincluding leftist authoritarian ruleand substantial political instability in the past. One such leader was President Lzaro Crdenas, who nationalized foreign oil holdings and expropriated 45 million acres of privately-owned farmland. Third, Mexico has also experienced revolutionary activity. The Zapatista uprising in 1994 was the most recent manifestation. During the 1960s and 1970s several guerrilla organizations plagued Mexicos countryside. Overall, Mexico possesses both the historical pedigree and the seeds of economic inequality that could allow for the rise of a radical left government.

Such a development would undermine the United States-Mexico partnership. A strong partnership is critically important for the United States. Mexico is situated between the United States and Latin America. With a population of 107 million people, Mexico is the third most populous country in the Western Hemisphere. Bilateral U.S.-Mexico trade now approaches $300 billion per year and 60% of Mexicos imports come from the United States. Mexico cooperates with the U.S. on a wide-range of matters ranging from the war on terrorism to law enforcement against the illicit narcotics trade. Under a radical left government, all this could change.

Venezuela offers a real-world model for such a government. President Chvez currently strives to be the architect of a bloc of Latin American states that would counterbalance U.S. policy and influence. Venezuela no longer cooperates in the war on terrorism. It uses its growing volume of petrodollars to finance leftist political movements in Latin America and promote Chvezs anti-American political philosophy in the global arena. Chvez has threatened to cut off his nations oil exportsapproximately 15% of the U.S. oil supplyto the United States. Most recently, he expressed support for Irans nuclear program.

Similarly, a radical Mexican government could employ oil as a weapon against the United States. With the largest oil reserves in Latin America, Mexicos oil leverage is enormous. At a time when the U.S. lacks a credible energy policy aimed at ending its dependence on oil, the U.S. is particularly vulnerable. Such a government could also legalize the possession of narcotics and end anti-narcotics cooperation with U.S. law enforcement agencies. The impact would be enormous. Up to 90% of Latin Americas U.S.-bound cocaine now passes through Mexico.

In the end, the issue of cross-border migration must be properly viewed as a bilateral United States-Mexico issue. The Presidents of both nations must work together to forge an agreed solution that would accommodate the core needs of both countries. In contrast, an unnecessarily draconian border-immigration policy could greatly elevate the risk of Mexicos being lost to the radical left. Then, the geopolitical costs sustained by the U.S. would far surpass even the most exaggerated estimates associated with todays broken borders.