David A. Andelman

President Trump's growing feud with Mexico is destabilizing our enormous neighbor to the South and putting our national security in grave jeopardy. If he's not aware of that, he should be.

Forget the cost of the wall or who might be paying for it. Forget America’s new tax code, or all the new Rust Belt jobs or all those other great benefits he contends we'll get from blowing up the North American Free Trade Agreement (NAFTA). Mexico is America’s third largest trading partner (after China and Canada), but the United States is Mexico’s #1. It sends 80% of its exports, worth more than $300 billion, to the U.S. That's about a quarter of its entire GDP.

So when White House press secretary Sean Spicer suggested that a 20% tax on all Mexican exports to the United States could yield enough revenue (several times over) to pay for the wall, he was right. White House chief of staff Reince Priebus soon walked it back, suggesting such a tax might be one of “a buffet of options.

But what a toxic buffet this could be. Taxing American companies to the point where they’d just close up shop in Mexico, and bring their jobs back here, could be catastrophic for Mexico. And not good for us, either.

Imagine for a moment that the 1.1 million Mexicans employed in American-owned companies in Mexico were suddenly to lose their jobs. Ultimately, that’s really what’s at stake here. The number of jobless there would surge by nearly 50%. Given the relative size of our two countries, that would be the equivalent of 3.3 million American workers suddenly thrown out of productive work. Could our economy stand that?

And the impact in Mexico would be far deeper, especially in a fragile nation recently emerging out of staggering poverty, with a deeply embedded criminal culture as well. Shuttered American plants in Mexico would send a shudder through the real estate industry, banks with outstanding loans or lines of credit to these enterprises. Millions, not only in these closed facilities but dependent on these workers spending their salaries, would lose their paychecks and their homes. The result would be social and economic chaos.

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Large swaths of Mexico’s fastest-growing communities, where General Electric and DuPont facilities elbow Whirlpool and Nabisco and major automakers, could become ghost towns overnight — their workers, catapulted into a nascent middle class in the past decade, suddenly destitute and desperate.

There are other components of the broad and deep ties that bind our two countries that are at stake. Mexicans in the United States sent $27 billion back home to their families last year, $2 billion more than the year before. If those payments were to be taxed or reduced, suffering would only be compounded in broad swaths of Mexico.

The first evidence of the potential impact of some steps under discussion was the behavior of the Mexican peso right after Mexican President Enrique Peña Nieto's tweet that he was canceling his visit to Washington, which had been scheduled for Tuesday. The peso plunged more than 1% in a matter of minutes.

If the Trump administration began jawboning American companies to close down their plants or make it financially impossible for them to continue producing south of the border for consumers to the north, it would be impossible to build a wall high enough or thick enough to keep out Mexicans suddenly stranded with no hope and no future.

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Deep cooperation among U.S. and Mexican law enforcement and intelligence agencies, who have joined in identifying and unwinding organized crime, drug cartels and potential terrorist threats, could also be a casualty of hasty and draconian measures that would do little to promote America’s national security.

As it happens, the immigrants crossing our southern frontier today are largely from Central America, which has its own social and economic problems. Multiply that ten-fold by adding newly jobless Mexicans, and the potential for chaos is incalculable. NAFTA was an agreement designed to stabilize our borders with Canada and Mexico. It was a small price to pay for a southern neighbor that is a strong, secure ally rather than a critically wounded threat.

David A. Andelman, a member of USA TODAY's Board of Contributors, is editor emeritus of World Policy Journal and author of A Shattered Peace: Versailles 1919 and the Price We Pay Today. Follow him on Twitter @DavidAndelman.

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