Nemesio Oseguera Cervantes, commonly known as “El Mencho,” was captured in Tapalpa, Jalisco, less than 100 miles south of the capital, Guadalajara. During the military operation, a battle ensued, and Oseguera was injured and passed away from his injuries on a military helicopter, at which point the decision was made to transfer his body to Mexico City for official identification. Oseguera was the leader of the Cartel Jalisco Nueva Generación, known as the CJNG.
CJNG cannot be understood as a single entity but rather as a network composed of distinct groups and alliances operating under the CJNG banner. Their alliance structure is top-down and hierarchical, meaning the killing of Oseguera will likely affect the organization and its alliances.
The CJNG was formed from the dismantling of the Cartel del Milenio, which oversaw the Sinaloa Cartel’s finances and expanded its operations into Mexico City. The arrest of the leader of Cartel del Milenio, Oscar Orlando Nava Valencia, as well as the death of “Nacho” Coronel, who provided them with security from the Sinaloa Cartel, caused a fragmentation to occur, of which one group, called los Torcidos, would emerge victorious and evolve into what we now know as the CJNG.
Recently, the CJNG has expanded across Mexico, contesting territory from the Sinaloa Cartel, which is currently facing internal ruptures following the arrest of “El Mayo” Zambada. The CJNG is considered the most powerful criminal organization in Mexico and has shown through force the extent of their arsenal and power as they battle over control of Michoacan and other key territories for the operation and expansion of their illicit activities.
The CJNG’s structure suggests it will be difficult for the organization to restructure peacefully. The more likely outcome is a fragmentation of the group in some form, either factions fighting over control of the network and its territories or a breakdown of several alliances under the CJNG banner.
The kingpin strategy has been used in Mexico’s war on drugs several times with similar results and unintended consequences. The kingpin strategy targets the leaders of major criminal organizations. In Mexico, this strategy was used to take down major cartel leaders, including the Beltran Leyva family, “El Chapo” Guzman, and, more recently, El “Mayo Zambada.” The killing of Oseguera represents a continuation of the kingpin strategy by both the Mexican and American governments.
The strategy holds that taking down the leaders will weaken the organization. The problem is that the unintended consequences of this strategy are generally tied to higher levels of fragmentation, violence, and diversification of crime. If history repeats itself, we can expect to see higher levels of violence across Mexico. The fragmentation of the cartel could cause instability in regions that had seen relatively low levels of violence, like Jalisco, Colima, Nayarit, and Aguascalientes, and reignite violence in contested territories like Michoacan, Tamaulipas, and Guanajuato.
Reportedly, that an alliance had been established between the sons of “El Chapo” and the CJNG to battle the “Los Mayitos” faction in Sinaloa, the killing of “El Mencho” could have a severe impact in Sinaloa. Los Mayitos could benefit from the reorganization and killing of El Mencho, and take the opportunity to take over more territory and control from “Los Chapitos,” reigniting violence in Sinaloa and possibly opening the possibility of reclaiming territory lost to the CJNG over the last decade.
The barricades and violence seen in the aftermath of the arrest and death of Oseguera were not just a reaction against the government, but it was also an important piece of signaling to other criminal organizations and their own alliances. It became a show of power to create fear among the population, but also to keep other criminal organizations and their own alliances in check. There were even reports that the CJNG used fake social media engagement to make the reprisal seem even bigger than it was and cause panic at Guadalajara’s airport.
Overall, we can expect a deterioration of the domestic security landscape in Mexico for the short to medium term as the CJNG and its alliances react and rebuild after the killing of Oseguera. The fragmentation of the CJNG into possibly smaller organizations and alliances is highly likely to cause an increase in violence, as well as even more diversification of criminal activity. Other groups like Sinaloa, who are amid their own fragmentation following the capture of “El Chapo” and “El Mayo,” may find an opportunity to reclaim lost territory, which will also likely mean the escalation of violence in contested territories spanning from Chiapas in the Southeast all the Way to Baja California Norte in the Northwest.
Many groups that work under the CJNG banner will have to decide whether to remain under the same banner or forge their own path, as the CJNG did in its conception. Regardless, the readjustments of alliances and fragmentations will likely result in higher levels of violence across the country while CJNG’s operations remain intact.
The potential spillover effects for the United States primarily concern security for citizens traveling to Mexico, who may be caught in the middle of these emerging territorial and control disputes. The Mexican government’s acknowledgment of the binational dimension of the special operation to capture Oseguera signals that it hopes this high-profile arrest will be seen as a tangible result of security cooperation. The Mexican President Sheinbaum and her advisors are under constant pressure to prevent the United States from taking unilateral military operations within Mexico. This killing should provide Mexico with the proof it needs that it can cooperate with the United States to battle crime with its own armed forces.
For U.S. policy, the operation underscores how deeply embedded American intelligence capabilities remain in Mexico’s counter‑cartel landscape. The White House’s acknowledgment of U.S. intelligence support fits within a broader pattern of President Trump’s second‑term posture, including FTO designations for groups like CJNG, expanded authorities for counter‑narcotics operations, and sustained pressure on Mexico to take more direct action against high‑value targets.
Mexico’s sensitivity to U.S. activity inside its borders is longstanding. Under President López Obrador, tensions spiked after the arrests of figures such as General Cienfuegos and former security minister García Luna, prompting threats to curtail U.S. law‑enforcement presence. President Sheinbaum, while politically aligned with Andres Manuel Lopez Obrador known as AMLO, has sought to stabilize the bilateral relationship. Her early interactions with the Trump administration, despite friction over tariffs and migration, reflect an effort to preserve cooperation while defending core sovereignty concerns.
Recent U.S. actions in Venezuela and Iran signal that the Trump administration is willing to conduct unilateral operations when it sees a compelling security interest. While a conflict following a potential cross-border raid into Mexico remains highly unlikely, even the perception that Washington might consider such an approach would carry significant political consequences. For Sheinbaum, the killing of El Mencho, especially with acknowledged U.S. intelligence involvement, reinforces the delicate balance she must maintain between cooperation with Washington and domestic expectations of sovereignty and peace.
