The Jews were 'colonists' who 'conquered' Palestine, says Koestler
Note the use of the words "colonizatory", "colonists" and "colonization" in the first two paragraphs. Aurthur Koestler uses these words unabashedly, for two reasons: (1) They accurately reflect the nature of the Zionist enterprise, and (2) "Colonialism", in 1949, was not yet a deprecatory term. Even in philosophical circles, it was still considered acceptable for a "progressive" (i.e. European) society to supplant a "backward" (i.e. Middle Eastern or African) society. And the "natives", needless to say, were still expected to be grateful for their conquerors' crumbs. Promise and Fulfilment: Palestine 1917-1949, by Arthur Koestler*, Papermac, 1983.
* Koestler was in Palestine in 1948 as a war correspondent for the Manchester Guardian. His book was first published in 1949 by Macmillan.