Shoah had earlier been used in the context of the Nazis as a translation of "catastrophe". For example, in 1934, when Chaim Weizmann told the Zionist Action Committee that Hitler's rise to power was an "unvorhergesehene Katastrophe, etwa ein neuer Weltkrieg" ("an unforeseen catastrophe, comparable to another world war "), the Hebrew press translated Katastrophe as Shoah .  In the spring of 1942, the Jerusalem historian BenZion Dinur (Dinaburg) used Shoah in a book published by the United Aid Committee for the Jews in Poland to describe the extermination of Europe's Jews, calling it a "catastrophe" that symbolized the unique situation of the Jewish people.   The word Shoah was chosen in Israel to describe the Holocaust, the term institutionalized by the Knesset on April 12, 1951, when it established Yom Ha-Shoah Ve Mered Ha-Getaot , the national day of remembrance. In the 1950s, Yad Vashem , the Israel "Holocaust Martyrs' and Heroes' Remembrance Authority" was routinely translating this into English as "the Disaster". At that time, holocaust was often used to mean the conflagration of much of humanity in a nuclear war.  Since then, Yad Vashem has changed its practice; the word "Holocaust", usually now capitalized, has come to refer principally to the genocide of the European Jews.   The Israeli historian Saul Friedländer wrote in 1987 of "the growing centrality of the Shoah for Jewish communities in the Diaspora" and that "The Shoah is almost becoming a symbol of identification, for better or for worse, whether because of the weakening of the bond of religion or because of the lesser salience of Zionism and Israel as an identification element".  The British historian Richard J. Evans wrote in 1989 that the term Holocaust was unsuitable, and should not be used.