In an open letter to the public in late July, several retired Border Patrol agents wrote on behalf of the National Association of Former Border Patrol Officers to warn that Mexican drug cartels are actively operating inside the United States spending millions every year to try to build their networks here. They argued that American politicians are protecting their activities as well. “Transnational criminal enterprises have annually invested millions of dollars to create and staff international drug and human smuggling networks inside the United States; thus it is no surprise that they continue to accelerate their efforts to get trusted...