B Before dawn on March 10, 2014, a group of roughly thirty migrants awoke in Tijuana, Mexico, packed their belongings, and ate one final meal before attempting to cross into the United States. Some were Mexican nationals who had previously been deported. Others were Central American women and children hoping to reunite with family members who had migrated north years earlier. There was nothing unusual about their intentions. For decades, foreign nationals with similar hopes had arrived at Mexican border cities to prepare for the journey into the United States. What distinguished this group was not why they wanted to cross, but how they intended to do it