There have long been arguments and debates over this border in political forums. It has evolved, however, into a symbol of humanitarian tragedy. Illegal immigration, what used to be a third-rail kind of subject in electoral politics, has developed into something altogether grim and tragic-a mass casualty event that has, largely, held both countries in its grip. Mass casualty us mexico border Sardrine migrants risk everything else about life to seek a better lot while deaths mount at the border, where cases of mass casualties are reported and have left in their wake sorrow, anger, and frustration.