Mexican military and National Guard troops search the embankment of the Rio Grande for smugglers in the Valley of Juárez on Feb. 5, 2025. The soldiers were deployed as part of the binational agreement between Mexico and the U.S. to avoid tariffs on Mexican exports to the U.S.

The Mexican troops will be posted to hot spots along the border with high rates of illegal migration and drug and weapons trafficking.

The deal reached this week by President Donald Trump and Mexican President Claudia Sheinbaum to postpone implementing tariffs appeared to be largely focused on stopping the importation of the synthetic opioid fentanyl — a goal that is of particular interest in San Diego and Baja California.