Mexico’s warring drug cartels helped orchestrate the massive influx of unaccompanied alien children that streamed through the Rio Grande Valley last summer, according to a leaked report from the Texas Department of Public Safety. Contrary to the narrative articulated by the Obama administration and promoted by major news organizations, the children did not enter the country entirely “unaccompanied.” How, when, and where the alien children crossed into the United States appears to have been determined by transnational criminal organizations who exercise control over much of the southern border, according to the leaked report first obtained by the Houston Chronicle. Intelligence...