Challenges and Opportunities for U.S.-Mexico Security Cooperation
The U.S.-Mexico relationship is one of the most fundamental for the security and prosperity of both countries. Economic and security conditions, governance, and public policy in Mexico directly impact the United States in a myriad of ways, from production chains integrating the two nations, to the flows of drugs and migrants across the U.S.-Mexico border. Reciprocally, the U.S. is Mexico’s largest trade and investment partner, while the demand for drugs from the U.S. and flows of guns purchased legally in the U.S., but smuggled illegally into Mexico, profoundly impact its security situation.
The election of Claudia Sheinbaum as Mexico’s President in June 2024 and the near-supermajority her leftist Morena movement has in the Mexican legislature, combined with the election of Donald Trump in the November 2024 U.S. elections and Republican control of both houses of the U.S. Congress, puts the neighbors on a course of significant potential conflict, even while maintaining a constructive relationship becomes more important for both. Difficulties are likely to emerge around the interdependent areas of migration and the border, drugs and security cooperation, Mexico’s legal framework and the treatment of U.S. investors, and activities by the People’s Republic of China (PRC) in Mexico in the context of the 2025-2026 review of the U.S.-Mexico-Canada Trade Agreement (USMCA).
President Sheinbaum and President-elect Trump began their relationship with a cordial November 2024 phone call. Sheinbaum’s leftist predecessor and mentor Andres Manuel Lopez Obrador (AMLO) successfully maintained a positive relationship with Trump during his first term despite frictions in the relationship. Nonetheless, this time, the combination of the gravity of the issues and the styles of the two leaders and their cabinets could lead to a less positive dynamic.
With respect to migration, Trump has pledged to secure the U.S.-Mexican border and begin large-scale deportations of migrants without legal status in the U.S. from the beginning of his administration. His promised initiatives include possibly declaring a state of emergency and using the U.S. military to deport migrants. Trump’s appointment of former Immigration and Customs Enforcement (ICE) director Tom Homan as his “border czar”, and South Dakota Governor Kristi Noem to head the Department of Homeland Security, suggests he is creating a team with the orientation and capability to support this intent.
Sheinbaum will likely push back on large-scale deportations by the Trump administration, particularly those involving Venezuelans and other non-Mexican citizens. The return of large numbers of Mexicans from the United States, possibly as many as four million, and the combination of negative symbolism, hardship from their dislocation, and the loss of remittances they previously sent to their families in Mexico, will likely put domestic political pressure on Sheinbaum to respond strongly, reducing the likelihood that her government would respond favorably to U.S. requests that Mexico help manage migrant flows through its own territory and allow migrants from other parts of the region to “Remain in Mexico,” as occurred during the first Trump administration.
Regarding drugs and security cooperation, Trump has threatened to impose significant tariffs on Mexico if it doesn’t do more to control flows of drugs into the United States, which contribute to over 100,000 drug overdoses in the country per year. Mike Waltz, nominated to be Trump’s National Security Advisor, a position that will imply significant physical access to the president and influence over national security policy, sponsored a resolution, as congressman, authorizing the U.S. armed forces to strike drug cartel targets in Mexico.
The incoming Trump administration is also likely to be less sympathetic than the Biden administration to issues of gun control on the U.S. side, although cooperation through the U.S. Bureau of Alcohol, Tobacco and Firearms (ATF) over the smuggling into Mexico of firearms legally purchased in the United States is likely to continue.
For its part, the Sheinbaum administration, although possibly disposed to combat cartels in Mexico more aggressively than her predecessor’s, is unlikely to revise its 2020 national security law, which created significant impediments to U.S.-Mexico cooperation narcotrafficking through the U.S. Drug Enforcement Administration (DEA) and other U.S. agencies.
With respect to Mexico’s legal framework, the 2024 constitutional reform passed by the Morena party to significantly revamp the nation’s judicial system has already prompted expressions of concern by the U.S., including by U.S. Ambassador to Mexico Ken Salazar. The business focus of the incoming Trump administration, and concerns regarding the treatment of U.S. companies in Mexico during his first administration, could re-emerge as a point of contention in the new Mexican judicial environment, particularly if Sheinbaum’s Morena party uses its supermajority in the legislature to make further constitutional or other changes in the legal framework which U.S. companies understood when committing to investments in Mexico.
Finally, Chinese investment in Mexico will likely become a matter of contention. Sheinbaum has indicated her interest in attracting more “nearshoring” investments to Mexico, including through tax breaks and the construction of infrastructure which makes such investments more attractive. PRC-based companies have already invested massively in Mexico, with the Rhodium Group identifying 700 separate initiatives involving $13 billion in Chinese investments in Mexico in 2023 alone. Trump has already indicated his concern over the PRC using facilities in Mexico as a way of circumventing tariffs and accessing the U.S. market through USMCA, and has threatened to impose significant tariffs on Chinese goods seeking to enter the U.S. in this manner. The review of USMCA in 2026, initially negotiated by the Trump administration during its first term, is likely to put further attention on the issue, and could even lead to a renegotiation or possible abrogation of the treaty.
Beyond these core issues, Mexico-U.S. relations are likely to be complicated by the interaction between the styles of its presidents and their cabinets. It is not clear whether Sheinbaum will have the same political skill or capital as did her predecessor, AMLO, to ignore rhetoric or actions by Trump that are seen as insulting or damaging to Mexico, particularly if U.S. actions toward Mexico such as tariffs and massive deportations are more severe than during the first Trump administration.
Reciprocally, it is not clear that Trump will feel a bond that leads him to be magnanimous in his dealings with Sheinbaum, in the way that he ultimately was with AMLO.
Beyond the two presidents, Mexico’s new foreign minister, Juan Ramon de la Fuente, brings to the government a vision shaped over many years as a professor at Mexico’s left-oriented National Autonomous University of Mexico (UNAM) of a more left-oriented country more disposed to challenge the U.S. on foreign policy matters. Indeed, Mexico has already attracted the ire of hawks in the U.S. by committing 312,000 barrels of oil and other support to help Cuba’s struggling government overcome its current energy crisis. Such gestures are likely to inspire significant pushback from incoming Secretary of State Marco Rubio and National Security Advisor Mike Waltz, both of whom have public records of pushing back against left-oriented governments in Latin America. While broad and deep policy clashes between the elected governments of Mexico and the United States in the coming years appear likely, the degree to which those tensions degrade the commercial relationship and security cooperation that is vital to both will depend on the forbearance and statesmanship of leaders on each side. However fruitful or negative the relationship becomes, neither the U.S. nor Mexico has the option to relocate to a different neighborhood.