I'm not inclined to go with the "lesser evil" argument with regard to the USA deciding to flex their military might by testing a weapon of mass destruction on the civilian population of a fishing village. More recently, a quarter of a million civilian lives were lost in the lraq War. Then there's that great American tragedy, Vietnam - a million Vietnamese civilians were killed, including 500 in the My Lai massacre where US soldiers gang-raped and slaughtered villagers. The individual held responsible for leading this massacre had his sentence commuted to three years "house arrest" by President Nixon
Hitler may have cheated justice but he did ultimately pay with his life, but it's not incorrect to state that that many other perpetrators of absolutely reprehensible acts of human slaughter do absolutely get away with it, often with people keen to defend this deed as "necessary" in some way, or some kind of "greater good".