Police detain suspects after dismantling a network that ran the finances and assets of the top leaders of the Mara Salvatrucha, or the MS-13 gang, in San Salvador. (Ericka Chavez/EPA)

For weeks, the Trump administration has been warning about the Central American caravan that is now stalled and waiting in camps just south of the U.S. border. Without substantiation, the administration warns that many of these migrants and refugees belong to criminal organizations, including MS-13.  

That’s not new. Since Donald Trump became U.S. president, he has regularly invoked MS-13, including in his second State of the Union address. His administration has focused on it, as well. In mid-October, for example, then-attorney general Jeff Sessions created a federal task force to fight transnational criminal groups, including MS-13, the Lebanese Hezbollah and the Sinaloa Cartel. 

So what is MS-13? Here’s what you need to know. 

1. MS-13 emerged in the United States 

The Mara Salvatrucha was formed in Southern California in the 1980s by children of Salvadoran immigrants who escaped their country’s 1979-1992 civil war 

The gang’s name derives from:  

  • Mara” means “gang” in Central American Spanish  
  • Salva” highlights their Salvadoran origins 
  • Trucha” is Spanish slang for savviness. 

In the early 1990s, Mara Salvatrucha (MS) became part of a regional gang alliance led by another street gang, the Mexican Mafia, or “la Eme.” As a result, MS added the number 13, which is the position of the letter M in the alphabet. 

In the early 1990s, El Salvador’s warring factions signed peace accords. Hundreds of thousands of Salvadoran exiles returned home. At the same time, the U.S. government deported close to 4,000 gang members with criminal records. But the Central American countries to which they were returned weren’t strong enough to curb their criminal activities; nor was the socioeconomic situation healthy enough to absorb the deportees into communities and jobs. MS-13 was able to recruit, expand and thrive. 

Currently, MS-13 has about 50,000 to 70,000 members, most concentrated in El Salvador, Guatemala and Honduras, known as the Central American Northern Triangle. According to 2009 FBI statistics, the latest official estimates, the United States has 8,000 to 10,000 MS-13 members. That’s less than 1 percent of the total gang membership in the United States. According to U.S. Customs and Border Protection’s estimates, between 2012 and 2017, 1 in every 5,000 minor migrants were “confirmed or suspected” to have an MS-13 affiliation.  

However, the United States doesn’t have recent or systematic data on gangs‘ membership or criminal activities. Consider the fact that the ’s latest estimates are from 2011, when it claims that there were “approximately 1.4 million active street, prison, and [outlaw motorcycle] gang members comprising more than 33,000 gangs in the United States.” Since then, the NGIC has used the 2011 estimates. Given the lack of systematic data, it’s difficult to conduct research or make policy that is based on evidence.   

2. How is MS-13 different in the Northern Triangle and the United States? 

As part of an ongoing research project into the nature and organization of MS-13 in the United States, we interviewed journalists and scholars, as well as law enforcement and public officials in the greater Washington area, which has a significant concentration of MS-13 members. We learned that there are marked differences between the gang in the United States and in Central America. 

In Central America, the gang is a semi-hierarchical organization, with cells or clicas at the lowest level, grouped into a regional programaLeaders from the programa, who tend to be in prison and older than the leaders of the clicas, compose the ranfla, the gang’s highest level. The ranfla does not necessarily direct the activities of everyone below them, as MS-13 tends to work in a franchise model. Still, in El Salvador, gang leaders negotiated with government authorities.  

In the Northern Triangle, MS-13 and Barrio-18, another powerful gang, compete with the government for power, at times controlling whole neighborhoods. They pay off corrupt public officials and exercise power through extortion, fear and brutal violence. El Salvador has been one of the most violent countries not at war, in part because of its gang violence. In response, the government helped broker a gang truce that lasted from 2012 until 2014. After the truce, homicides decreased dramatically — but by early 2014, murder numbers were back to pre-truce levels. 

In contrast, in the United States, MS-13 is a fragmented organization without a clear hierarchy. Researcher José Miguel Cruz, for instance, characterizes it as “a federation of teenage barrio cliques that share the MS-13 brand.” Without much domestic and transnational leadership, U.S. cliques compete against one another. This limits collective action, making it difficult for them to carry out large-scale criminal activities and bring in steady revenue. 

In the United States, MS-13 cliques have also committed heinous homicides. However, in the United States, only 13 percent of homicides are gang-related, a far lower proportion than the 40 percent of homicides in the Northern Triangle. 

More important, their crimes are on a much smaller scale. Rather than controlling whole communities, according to our interviewees, in the United States, MS-13 has focused on threatening and extorting members of the Latino community in a few areas, including the suburbs of Washington, New York, New Jersey, Boston, Houston, Los Angeles and the San Francisco Bay area.  

3. MS-13 is not a transnational drug cartel 

Some MS-13 activities are transnational, including drug and human trafficking, money laundering and migrant smuggling. But it’s not very effective at any of these. Rather, their clicas are opportunistic, occasionally working for drug cartels and other powerful gangs. In the United States, the clicas are at the bottom of the distribution network, handling small-scale drug-dealing in neighborhoods and schools controlled by other gangs.

Guadalupe Correa-Cabrera (@gcorreacabrera) and Mariely López-Santana (@marielylopezsare associate professors at the Schar School of Policy and Government at George Mason University, where Camilo Pardo (@Pardo96_) is a PhD candidate.