Eric Olson, the associate director of the Latin America program at the Wilson Center, said the new arrivals from El Salvador formed MS-13 as a form of self-preservation to compete with other Los Angeles-based gangs.

“The Salvadorans were suddenly confronted with Mexican gangs in the high schools, and African-American gangs, so almost as a self-protection thing, they formed cliques and gangs,” Olson told The Daily Signal.

Olson and other experts say MS-13 expanded when, in the mid-1990s, the U.S. government changed immigration law to hasten deportation of the gang’s members back to El Salvador.

MS-13 became the first street gang to be labeled a “transnational criminal organization”—one that operates internationally—by the U.S. government.

“While many of the gang members eventually got deported, they had to reconfigure themselves in El Salvador, and so you had a very vulnerable population fall back on their larger gang family [there] as a protection mechanism,” Olson said. “MS-13 became bigger and more powerful in El Salvador.”

Nelson Arriaga, president of the International Latino Gang Investigators Association, which provides training to law enforcement conducting anti-gang operations, says the U.S. government did not give proper support to Salvadoran authorities who were ill-equipped to handle the return of their troubled nationals.

“Law enforcement in Central America were completely oblivious to the criminal element being exported from the U.S. to those countries, and to the level of sophistication gang members were bringing with them,” Arriaga told The Daily Signal in an interview.

“Those countries were fertile for gang proliferation.”

As MS-13 grew its ranks from deportees returning from the U.S. to El Salvador, members also migrated back to the U.S.

“When we started deporting them, some would turn around and come right back,” McBride said. “It became a circular problem.”

Enforcement Crackdown

Today, the Justice Department estimates that MS-13 has roughly 30,000 members worldwide and more than 10,000 in the U.S. MS-13 is active in 40 states plus the District of Columbia, the department estimates, with an especially significant presence on the East Coast, in New York, Virginia, and Maryland.

While Trump has blamed the Obama administration’s less strict immigration policies for MS-13’s growth, a Justice Department fact sheet, dated April 18, credits “great progress made” by federal, state, and local law enforcement in “diminishing” and disrupting the gang’s impact during 2009 and 2010.

Indeed, McBride says he does not blame the Obama administration for the spread of MS-13. The California gang expert notes that President Barack Obama’s Treasury Department in 2012 sanctioned the gang as a transnational criminal organization.

In January 2016, the Justice Department indicted 56 MS-13 members in the Boston area on federal racketeering conspiracy charges, some related to murder, conspiracy to commit murder, attempted murder, and drug trafficking. In March of this year, the U.S. Attorney’s Office for the Eastern District of New York indicted more than a dozen MS-13 members in seven killings on Long Island spanning three years, including the deaths of several high school students last year.

The FBI started an MS-13 National Gang Task Force in 2004 to coordinate the investigative efforts of federal, state, and local law enforcement agencies against the gang.

Arriaga, a retired sergeant in the Inglewood Police Department who focused on gangs, says the FBI and U.S. Immigrations and Customs Enforcement agents today are embedded in Central America to help local police in those countries deal with the MS-13 threat.

“The MS-13 threat in Central America is on steroids compared to the threat here,” Arriaga said. “It’s good to see the Trump administration making greater emphasis of MS-13, but the enforcement aspect of this has already been there.”

Threat ‘Stays Here’

Despite these efforts, law enforcement experts acknowledge that MS-13 remains strong.

Gang members in the U.S. have preyed on recent arrivals from Central America, many of them teenagers who traveled here alone in a surge of illegal immigration from El Salvador, Honduras, and Guatemala over the past few years.

“The best way to tackle the problem is to convince young people to stay away from the gangs,” Sessions said during his April 28 speech in Long Island.

While MS-13, which has a decentralized structure with little coordination, is not considered a major player in international drug smuggling, Olson said, the gang uses extortion to control local drug markets.

“Extortion is really their bread and butter, so if you are in a poor neighborhood and your job isn’t paying enough, or you don’t have a job and sell tortillas on the corner, [MS-13] force you to pay a tax,” Olson said. “They are extorting all economic activity. Their control of legal markets and extortion is absolute. And when they are in conflict with one another and the police, they become extraordinarily violent.”

Olson called for a multipronged strategy to defeat MS-13:

It’s not like removing a tumor, where you can cut it out and it’s gone. It stays here. Anti-gang work in the U.S. and in Central America needs to go way beyond simply trying to deport and incarcerate people. I wouldn’t say border security won’t have any impact. It’s already had a big impact. It’s one element of an overall challenge.