Overview

Background

Sheinbaum is the granddaughter of Jewish immigrants from Eastern Europe and the child of two scientists who participated in the 1968 student movements in Mexico City. She studied at the Universidad Nacional Autónoma de México, earning a bachelor's degree in physics, a master's in energy engineering, and a doctorate in environmental engineering; her dissertation focused on energy consumption trends in Mexico, and she conducted doctoral research at the University of California's Berkeley Lab. She is one of the scientists and policymakers who shared the 2007 Nobel Peace Prize for their work on the United Nations Intergovernmental Panel on Climate Change.

Sheinbaum first entered politics in 2000, serving as Secretary of the Environment for Mexico City under López Obrador's administration as mayor. She subsequently served as head of government of Mexico City from 2018 to 2023. She secured her presidential victory with nearly 60 percent of the vote — the highest percentage ever for a Mexican presidential candidate. A close ally of MORENA founder and former president López Obrador, she came into office pledging continuity with the populist left-wing movement he built, while also cultivating her own identity as a technocratically minded administrator with scientific credentials unusual in Mexican politics.

Public Role in the Second Trump Administration

The Tariff Standoff and Diplomatic Strategy

Sheinbaum's relationship with the Trump administration began under duress. Before Trump was even inaugurated, his threat to impose 25 percent tariffs on all Mexican goods forced her hand. Given the extraordinarily high stakes for both countries politically and economically, the Sheinbaum administration adopted a pragmatic strategy, repeatedly calling for respectful, ongoing diplomatic negotiations — setting her apart from other leaders in the Western Hemisphere who opted for a more confrontational tone. She indicated that Mexico would continue to collaborate but would not become a subordinate of the United States, and her cool-headed approach prioritized protecting Mexicans living in the United States while scaling up capacity to receive Mexican returnees.

When the Trump administration formally initiated tariff action on February 1, 2025, Sheinbaum initially said Mexico would enact retaliatory measures; but on February 3, one day before they were set to take effect, both leaders negotiated a one-month delay. On March 6, Trump exempted goods compliant with the United States–Mexico–Canada Agreement from tariffs. As a result, roughly 84 percent of Mexico-U.S. trade remained tariff-free as of mid-2025. Mexico has not implemented any retaliatory tariffs on imports from the United States.

Following Trump's hardline rhetoric and economic coercion, Sheinbaum opted for diplomacy over confrontation. Rather than retaliate, she voiced confidence that Mexico could negotiate better conditions, and her administration actively pursued a strategy of de-escalation through swift diplomatic engagement and increased enforcement actions on migration and narcotics. In July 2025, Trump wrote to Sheinbaum stating that the United States would increase tariffs under the International Emergency Economic Powers Act to 30 percent due to the ongoing fentanyl crisis, but later announced a 90-day pause. As of early 2026, the pause has continued, with the IEEPA tariff rate for imports from Mexico remaining at 25 percent.

Cartel Policy and Security Cooperation

On security, Sheinbaum has delivered significant concessions to Washington while holding firm on a core principle of sovereignty. When six Mexican cartels, including the Sinaloa Cartel and Cartel Jalisco Nueva Generación, were designated as Foreign Terrorist Organizations, Mexico carried out one of the largest single transfers in bilateral history, sending 29 cartel figures to U.S. custody; by January 2026, the total number of alleged cartel figures transferred had reached 92 since Sheinbaum took office.

The progressive Mexican leader walked a careful line with Trump for more than a year, addressing provocations with a measured tone and meeting U.S. requests to crack down on criminal cartels more than her predecessors, in an effort to offset threats of tariffs and U.S. military action against the gangs. Mexico also allowed U.S. surveillance drone flights over its territory and agreed to coordinated patrols along the border with the U.S. military. Yet Sheinbaum drew a firm red line at boots on the ground, unequivocally rejecting proposals for U.S. troops to operate inside Mexico.

Migration Management

Migration became the central lever of the bilateral relationship almost immediately. After an early phone call between the two leaders, Sheinbaum and Trump offered differing accounts of what was discussed regarding migration; Trump claimed Mexico had agreed to effectively close the southern border, a characterization Sheinbaum denied. In practice, Mexico substantially increased enforcement along its own southern border and deepened cooperation on migrant interdiction, providing the Trump administration with tangible results even as Sheinbaum avoided framing the policy in terms Washington preferred. Her strategy successfully buffered tariffs and other possible conflicts without explicitly articulating what new migration policies Mexico was willing to undertake.

Third-Country Trade and Supply Chain Policy

One significant and underappreciated dimension of Sheinbaum's economic diplomacy has been her effort to demonstrate to Washington that Mexico is not a backdoor for Chinese or other third-country goods into the North American market. Ahead of the 2026 USMCA review, the Sheinbaum government announced that effective January 1, 2026, it would impose a 50 percent tariff on over 1,000 products imported from countries with which Mexico does not have a free trade agreement, including India and China. The move was widely read as a gesture aimed at satisfying U.S. concerns about supply chain integrity as the formal trade review approached.

Recent Developments

The bilateral relationship shifted onto rockier ground in the spring of 2026. Reports emerged that two CIA agents were killed in a car accident during an operation to dismantle a drug laboratory in the Mexican state of Chihuahua; Sheinbaum's government claimed to have no knowledge of the agents' presence inside Mexico — a potential violation of sovereignty and the Mexican Constitution — and the incident set off alarm bells given Trump's threats to send ground troops into the country.

In the wake of mounting deaths of Mexican citizens in U.S. immigration custody, and the Trump administration's decision to impose an energy blockade on Cuba — a key Mexican ally — Sheinbaum took a harder line. The main point of contention became Cuba: solidarity with the U.S. adversary has long been a cornerstone of Mexico's political ethos. A January 2026 executive order may impose tariffs on any country that sells oil to Cuba, and Mexico has supplied oil to Cuba, adding a new point of friction.

The USMCA, the backbone of North American trade, entered its formal review process starting in July 2026. What was once expected to be a routine assessment has become a high-stakes negotiation, with the Trump administration poised to seek additional concessions from Mexico and Canada on trade disputes while leveraging the review to address migration, drug trafficking, and continental defense. Sheinbaum has addressed the review directly, arguing that the pact remains valid through 2036 with annual check-ins even if Washington does not confirm an extension on schedule.

Outlook

Sheinbaum enters the second half of her term with her domestic standing relatively intact and her international profile considerably elevated, but facing deepening structural tensions with Washington that her diplomatic strategy can only partially contain. She faces pressure from Trump amid his increasingly changing and erratic demands to battle drug cartels while he holds the threat of tariffs over Mexico. Each concession Mexico has made has been met not with reciprocal relief, but with a new demand, a dynamic that is testing the limits of her pragmatic approach.

The World Bank projected Mexico's economic growth would slow to under one percent for 2026, citing uncertainty surrounding tariffs and the USMCA review; the projection underscored how Mexico's economic trajectory remains tightly bound to North American trade dynamics and U.S. policy decisions. The USMCA review is now the most consequential near-term test of her presidency. She has earned notable praise for how she has managed the U.S. relationship, but the combination of unresolved tariff pressure, sovereignty disputes over cartel operations, and the Cuba issue has made the bilateral environment more volatile than at any point since she took office. Whether her strategy of calibrated accommodation can continue to hold — without fracturing her domestic political coalition or triggering an irreversible escalation from Washington — is the defining question of her presidency's next phase.