Read up on the Jalisco New Generation Cartel...
It arose as a break-away cartel. It had a militia division.
From what I've read that division, though mostly ex-Mex armed services, has some ex-US military at the head of it.

Per Gemini

The rise of the Jalisco New Generation Cartel (CJNG) is a complex story rooted in the shifting dynamics of Mexican drug cartels. Here's a breakdown of its key origins:  

Splintering of the Milenio Cartel:
The CJNG emerged from the remnants of the Milenio Cartel. This cartel, once allied with the Sinaloa Cartel, began to fracture following the capture of its leaders and the death of key figures like Ignacio "Nacho" Coronel.  
This power vacuum created an opportunity for new factions to emerge.
"El Mencho" and Leadership:
Nemesio Oseguera Cervantes, known as "El Mencho," played a crucial role in consolidating these splinter groups into the CJNG. His leadership and strategic vision were instrumental in the cartel's rapid expansion.  
Exploiting Power Vacuums:
The CJNG capitalized on the internal conflicts and weakening of other cartels, including the Sinaloa Cartel and Los Zetas.  
This allowed them to expand their territory and control lucrative drug trafficking routes.
Tactics and Violence:
The CJNG gained notoriety for its extreme violence and aggressive tactics. They have been known to engage in open confrontations with Mexican security forces, demonstrating a willingness to use significant firepower.  
Their use of brutal tactics, including public displays of violence, has been used to intimidate rivals and establish dominance.  
Diversification of Criminal Activities:
Beyond drug trafficking, the CJNG has diversified its criminal activities to include extortion, kidnapping, and other illicit ventures, increasing its revenue streams.  
In essence, the CJNG's rise is a story of opportunistic expansion, strong leadership, and brutal tactics, all occurring within the context of a volatile and ever-changing criminal landscape in Mexico.  


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