Denial is defensively protecting information from being shared with other historians, and claiming that facts are untrue – especially denial of the war crimes and crimes against humanity perpetrated in the course of the World War II (1939–45) and the Holocaust (1933–45). The negationist historian protects the historical-revisionism project by shifting the blame, censorship, distraction, and media manipulation; occasionally, denial by protection includes risk management for the physical security of revisionist sources.