Trump often blames Obama-era immigration policies for the rise in MS-13, but the gang’s origins are believed to date back to Los Angeles in the 1980s, where thousands of Salvadoran immigrants landed after fleeing their country’s civil war, according to Héctor Silva Ávalos, a research fellow at the Center for Latin American and Latino Studies at American University. Young immigrants formed the Mara Salvatrucha gang in search of protection and identity, Ávalos said. When the U.S. government put mass deportation policies in place in the mid-1990s, he added, many of these gang members returned to war-torn countries in Central America, where gang activity only prevailed

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