The holocaust

so im pretty into the holocaust and the whole nazi regime in its entirety. what interests me most is the concept that the world saw its greatest evil when everyone worked together toward a common goal. its makes me wonder why we cant unify for something more beneficial to the world. anyway im watching this documentary on auschwitz on netflix and some of this stuff is pretty crazy. like imagine an ss officer assigned to a death camp...your probably thinking a tall athletically thin german man with light colored hair with a face with sharp lines to sort of suggest a grim appearance and a pristinely crisp uniform...in reality these guys were so relaxed about their jobs and drunk a lot of the time. its crazy to think how many people died in this whole event. like the way i see it, even if everyone i've ever known was killed then it still would hardly scratch the surface. crazy stuff