The issue of why Auschwitz concentration camp was not bombed by the Allies during World War II continues to be explored by historians and Holocaust survivors. Michael Berenbaum has argued that it is not only a historical question, but "a moral question emblematic of the Allied response to the plight of the Jews during the Holocaust." David Wyman has asked: "How could it be that the governments of the two great Western democracies knew that a place existed where 2,000 helpless human beings could be killed every 30 minutes, knew that such killings actually did occur over and over again, and yet did not feel driven to search for some way to wipe such a scourge from the earth?" During his second visit to the Yad Vashem Holocaust memorial in Jerusalem in 2008, U.S. President George W. Bush said