Yet awareness of historical events can be fleeting. The facts of Adolf Hitler's systematic plan to exterminate the Jews won't ever be erased — but could be forgotten. Details can recede as time passes, diminishing the power of a universal lesson about man's capacity for evil. A new study released by the Conference on Jewish Material Claims Against Germany found that 31 percent of Americans, and 41 percent of millennials, think only 2 million Jews were killed in the Holocaust. Additionally, 11 percent of U.S. adults, and 22 percent of millennials, said they haven't heard, or are not sure whether they have heard, of the Holocaust. And 40 percent of adults, and 66 percent of millennials, can't identify Auschwitz as a Nazi death camp.