Officials in the United States might be tempted to view the disturbing surge in young refugees as simply a border security issue. But the problem is far more complex than that — the drug cartels are now major players in Central American countries, driving vulnerable populations northward to the United States to enhance their own profits.

And America’s hardline prohibitionist drug war is only making things worse.

Although the growing power of the cartels is not the only factor accounting for this crisis, Secretary of Homeland Security Jeh Johnson suggested in congressional testimony that the “push factor” of violence is important.

Drug gangs have gained control of major chunks of Central America, making honest economic activity perilous. Teenagers especially have few options if they are not willing to work for the drug lords. As Caitlin Dickson noted in the Daily Beast, for example, “by making these countries so dangerous and virtually unlivable for its poorest citizens, the cartels have effectively created an incentive for people to flee, thereby providing themselves with more clientele for their human smuggling business.”

Since the cartels have seized control of human smuggling routes through Mexico, often charging refugees several thousand dollars for passage, the flood of undocumented immigrants significantly supplements the revenue that the drug gangs have long enjoyed from trafficking in illegal drugs. Would-be immigrants who can’t pay are pressed into service to carry drugs into the United States. And the surge of unaccompanied minors helps distract the already strained U.S. Border Patrol, making it easier for the drug lords to avoid having their products intercepted.

All of these problems have been building for years. As the Mexican government stepped up its attacks on the cartels, drug kingpins began moving many of their operations into Central America as early as 2008. Such geographic displacement is a recurring problem with the prohibitionist strategy directed against illegal drugs. Since the drug trade is illegal, its practice in the black market is enormously profitable, and traffickers go to great lengths to maintain their power and market share. Whenever pressure mounts in one arena, they simply relocate to another jurisdiction where the risks and problems are, at least temporarily, less imposing.

Central American countries already had some of the highest homicide rates in the world, but the arrival of the Mexican cartels has made a bad situation even worse. Drug gang turf fights that plagued Mexico over the past decade are now being played out with increasing frequency and ferocity in its southern neighbors. And the same gruesome trophies, especially severed heads, are now showing up with greater frequency as well, increasing the incentive for honest and vulnerable young people to leave.

Already by December 2010, Guatemalan President Álvaro Colom had declared a “state of siege” in Alta Verapaz, an especially violent province near the border with Mexico, contending that the Zetas had overrun that province. Another Guatemalan official later asserted that the cartel controlled three other states — nearly half of Guatemala’s territory. Kevin Casas-Zamora, a former vice president of Costa Rica and later a fellow at the Brookings Institution, has cited cartel dominance in a large northern region known as the Petén. “The Zetas have roadblocks there,” he has noted. “You can only enter the Petén if the Zetas allow you to.”

Similar developments took place in Honduras. Journalists reported how traffickers dominated the rural portions of the country, including Colon Province. The reputed local drug kingpin traveled the area freely, but ordinary farmers were fleeing the province in droves, and the local press had become wary about reporting on cartel activities. By nearly all accounts, the power of the cartels and the extent of drug-related violence in both Guatemala and Honduras remain at extremely high levels.

Advocates of drug policy reform in the United States and Latin America, including former presidents of Mexico, Colombia, and Honduras — and the current president of Uruguay — point out that the current prohibitionist approach to illegal drugs empowers and enriches criminal cartels. Former Mexican President Felipe Calderon for his part seemed to imply back in 2011 that decriminalization of drugs might “annul the stratospheric profits of the criminals.”

But the reality is that unless we heed those warnings, we will continue to see the truly disturbing effects of prohibition, whether in the form of violence in Latin America or a refugee crisis along the U.S.-Mexico border.