By Trashing Mexico, Trump Hurts the U.S.

Without Nafta, American businesses would lose protection from populism south of the border.

 In contrast, Mr. Trump’s approach seems almost designed to help elect an anti-American, pro-Castro populist, Andrés Manuel López Obrador, to the Mexican presidency in 2018.
.. Today’s illegal immigrants are coming primarily from Central America. Washington should cooperate with Mexico to create a multistage defense. Working with Mexico to strengthen law enforcement, the rule of law, and intelligence would leave both countries better positioned to stop drug traffickers, criminals, human smugglers and terrorists.Insulting Mexico, on the other hand, will make it impossible for politicians there to work with Yankee gringos. A hostile Mexico can ignore the flow of people northward, while American policies that weaken investment and growth in Mexico simply create more incentives for Mexicans to migrate to the U.S.

.. Mr. Trump’s great wall would be a waste of money, as conservative Republicans from border states now acknowledge. A combination of fencing, additional border police, electronic surveillance and other intelligence tools would stop illegal immigration more effectively and at a lower cost.

.. because Nafta’s energy terms refer to Mexico’s constitution, American investors are now protected against a populist reversal of Mexican policy—but only as long as the U.S. remains in Nafta.
.. U.S. producers seeking to compete with Asian and European manufacturers now transfer components across North American borders up to 14 times in the process of completing final goods. More than 30% of Mexico’s exports to the U.S. contribute to the integrated auto sector.
..Yet when the Manufacturers Alliance for Productivity and Innovation recalculated trade statistics to count only the value added by each country, the U.S. had a surplus in manufactured goods with Mexico and Canada.
.. Six million U.S. jobs depend on exports to Mexico, with workers in Texas, Michigan, Arizona and Louisiana particularly vulnerable to self-defeating economic nationalism.
.. the alliance of the three North American democracies—being energy self-sufficient with integrated infrastructure and efficient and secure borders—could offer the U.S. a resilient and powerful base from which to face global challenges.
.. William Seward, Lincoln’s secretary of state and the man with the vision to purchase Alaska, wrote in 1853 that someday Mexico, Canada and the U.S. would create a North American union, but only after a long process and solely through free choice. Seward fought for America’s national union while also promoting an internationalist vision.