In the early morning hours Monday, on a remote road near the Texas-Mexico border, Mexican marines picked a deadly and rotten piece of fruit when it captured Miguel Angel Treviño Morales, the sadistic boss of Los Zetas criminal cartel. Los Zetas appeared on the scene in 1999, an elite unit of the Mexican military that went rogue, working at first for the Gulf drug cartel and eventually breaking off to form their own criminal organization known for employing extremely brutal methods of torture, terror and mass murder. Los Zetas quickly became a major force in Mexican drug trafficking.

Drug cartels existed long before the passage of the North American Free Trade Agreement (NAFTA) in 1994, but not drug cartels as we know them today. As we approach the 20th anniversary of NAFTA, we can no longer ignore its contribution to building a powerful and violent criminal enterprise that has brought Mexico close to being labeled a failed state and made the Mexican-U.S. border into a war zone.

Most often when we analyze trade agreements, the focus is on trade volumes, jobs and manufacturing statistics, poverty levels and immigration—all extremely important ways to understand the impact of neoliberal policies bequeathed to us from Ronald Reagan and Bill Clinton. But to fully appreciate how devastating free trade has been, we need to look more closely at the aftermath of free trade on the bonds that hold communities together. It starts out small, a single thread that eventually leads to unraveling the whole cloth.

Take the dumping of below-cost-of-production corn from the U.S. into Mexico, which happened in full force following the passage of NAFTA. After a few years of not making any money on their small farms, Mexican peasants started moving off the land, leaving whole villages empty except for those too old to leave. This massive expansion of economic migrants was fueled by the lure of jobs in the new maquiladoras, light manufacturing businesses on the border, operating in “free trade zones.” The supply of workers far outweighed the available jobs. These unemployed and displaced young Mexicans were vulnerable to the drug cartels who recognized early on the opportunities created by NAFTA for the unregulated movement of goods across the border—including drugs and illicit cash.

Life in this environment became very cheap. Piles of bodies started to appear in border towns. Hundreds of young woman started to disappear in towns like Tijuana and Ciudad Juárez, and only occasionally showing up as bleached bones in the desert. Corruption and violence invades all aspects of life. The police, judiciary, financial institutions, media, businesses and elected representatives of the government are all at risk and threatened.

Now, nearly twenty years after NAFTA was passed, we read the story of the arrest of a crime boss driving his pickup on a country road carrying two million in walking around money as he goes to visit his family. If we are willing to follow the story back we will meet thousands of Mexican peasants forced off their farms, and just as many young women sitting at sewing machines making running suits and baseball caps, all just a drop of a thread away from becoming foot soldiers in the drug trade. Their farm communities are still empty, devastated, and as often as not, under the control of the cartels. As we contemplate new and bigger free trade deals, with innocuous names like the Trans Pacific Partnership and the Transatlantic Trade and Investment Partnership we should think carefully about the fruit that NAFTA created and what free trade has done to destroy the bonds the hold communities together around the world.