Mexico’s war on drugs is a long and hard-fought conflict which has resulted in over 60,000 deaths. Drug cartels rake in billion of dollars a year in revenue, and with that money comes a great deal of power. Many Mexican cartel members arm themselves with modern automatic rifles trafficked from the United States, as well as other military-grade equipment. But there is a more insidious form of power wielded by the cartels: the recent disappearance of 43 students in September illustrates how much influence the cartels exert over local governments. Often times, poorly paid and relatively uneducated municipal police are easily coerced and incorporated into the very system they are intended to fight. According to the Mexican government, police officers are wired a staggering $100 million in bribes every month.

In the face of such massive collusion, it is no surprise that the Mexican government is reluctant to employ local police forces in operations. Instead, the Mexican Army is often relied upon. Generally viewed as more clean and operationally capable, the Mexican Army has taken on many tasks normally carried out by the police forces.

However, the Mexican Army has also been permeated by cartel influence, with some battalions so compromised that the US government has refused to provide them with assistance. With its army and police not consistently clean, who can the Mexican government turn to for high-stakes operations such as raids on cartel bosses or massive drug seizures?

The answer, as it turns out, is the Naval Infantry Force, also known as the Mexican Marines.

Unlike the army and police, the Naval Infantry are loyal, well trained, and consistently effective. Much smaller (20,000 vs. 200,000 troops) and more prone to scrutiny than the Mexican Army, the Naval Infantry Corps. is less susceptible to outside influence. The Mexican Marines are also well-trained and disciplined; much of the training and assistance provided by the US goes to the Mexican Navy (which the Naval Infantry is part of). Being an amphibious rapid reaction force, the Naval Infantry Corps. is well-equipped to conduct time-sensitive raids and deploy rapidly on fleeting targets of opportunity.

Perhaps as a result of familiarity, they are also are more receptive and cooperative with the US than the Mexican Army. This cooperation includes conducting operations based on tips by the US intelligence community, which has increased the trust between US agencies and the Mexican military.

These attributes have payed dividends to the Mexican Naval Infantry, whose combat abilities have been showcased in prominent high-stakes operations such as the recent re-capture of El Chapo. The success of the Naval Infantry illustrates how crucial training and experience are in asymmetrical operations. While inexperienced militaries such as the Iraqi Army in 2014 often crumble in the face of minimal resistance, small and dedicated expeditionary forces frequently triumph in the type of asymmetrical combat common not only in Iraq and Syria but also in crime-plagued Mexican areas. The success of the Naval Infantry is not an anomaly but part of a larger trend towards placing an outsize emphasis on the role of elite forces, a trend which includes Obama’s continued employment of US special forces in Iraq, Syria, and Afghanistan.

Of course, small rapid-reaction forces are only a small component of a wider solution. Capturing a drug kingpin is a far cry from dismantling the whole cartel, and the more numerous Mexican Army and Federal Police are crucial in day-to-day operations, as the Naval Infantry can only cover so much ground. Nevertheless, the Mexican Marines have cemented their status as a consistent and effective arm of the Mexican security apparatus; their operational successes illustrate the importance of training and professionalism, even in low-intensity operations against cartels.