Last December, the rumor running through the Mexican political class was that President Andrés Manuel López Obrador wanted to throw the U.S. presidential election to Donald Trump.

Blaming a cash shortage, the Mexican migration authority had essentially stopped intercepting migrants moving north through its territory toward the United States. Migrant encounters with U.S. agents at the southern border surged to over 300,000, the highest monthly tally on record. Republicans had a field day accusing the Biden administration of allowing chaos at the border.

“López Obrador had the key to the White House,” noted Rafael Fernández de Castro, who directs the Center for U.S.-Mexican Studies at the University of California San Diego. “If migrant flows had stayed at the same levels of 2023, it would have sunk the Democrats.”

But they did not. Just after Christmas, President Joe Biden dispatched Secretary of State Antony Blinken and Homeland Security Secretary Alejandro Mayorkas to Mexico City, and the Mexican government found the wherewithal to help. By January, migrant encounters with U.S. Border Patrol agents had fallen to 176,000. By August they had declined to under 108,000.

Follow Eduardo Porter

Political observers remain a little puzzled about the Mexican president’s seeming about-face. A self-proclaimed champion of the left, AMLO, as he is........

© Washington Post