The outbreak of the Arab-Palestinian-Israeli war in 1948 was a kind of tsunami for the entire Middle East, with repercussions that are still visible even on a global level. It was not the beginning of the longest conflict in contemporary history, but rather the final phase of a clash that began at least six decades earlier. The lesson sheds light on the deepest roots of this background, rewinding the thread of the discussion around a concept that links that tragic past to a dire present: "refusal". We will talk about: Palestine at the turn of the twentieth century. It is estimated that in the Palestine of the 1860s there were approximately 411,000 individuals. Who were these people? Where did they live and how did they perceive themselves? "Refusal" and "separation". In 1907, the Eighth Zionist Congress created a department for the colonization of Palestine, sending Arthur Ruppin to this end. His goal was to create "a Jewish environment and a closed Jewish economy, in which producers, consumers and intermediaries are all Jews." The concept of "rejection" was very present in Ruppin's approach and mentality. Physical and mental walls. The first "structural clashes" between the different communities were recorded in Jaffa in March 1908, and continued in the following years. In just two decades, there were far more cases of mass violence than in the entire previous four centuries. The first political murder in the Zionist community in Palestine. Jacob Israel de Haan (1881-1924), a Dutch jurist who strongly opposed some aspects of Zionism, was the victim of what is considered the first political murder within the Zionist community in Mandatory Palestine. His murder is the mirror of fractures full of meanings. The extra-territorialization of the land. The issue of the extra-territorialization of Palestine was the one that most struck the British envoy John Hope-Simpson during the inspections he carried out there in 1929. In this regard he noted that "The result of the purchase of land in Palestine by the Jewish National Fund is that the land has been extraterritorialized. It ceases to be land from which the Arab can draw advantage, now or at any time in the future." As of December 1946, the year of the last official survey carried out on the matter, the amount of land purchased by Zionist organizations corresponded to 6 percent of the total land subject to the partition suggested by the UN. Rapporteur Lorenzo Kamel (1980) teaches Contemporary History at the University of Turin. He has held teaching and research positions at numerous universities in the Middle East, Europe, and the United States, including Harvard University, where he was a four-year associate. He was a Marie Curie Experienced Researcher at the Albert-Ludwigs-Universität Freiburg and received the Palestine Academic Book Award, the Giuseppe Sciacca International Prize, and the Fritz Thyssen Grant. He has published 15 books (8 of which as an author) on topics related to the Middle East, the Mediterranean, and Global History. In addition to being a columnist for «Al Jazeera», «Il Manifesto» and other Italian and foreign newspapers, he is a member of the editorial board of the magazine «Passato e Presente».