1943 de-classified CIA document – it is highly educational – see link below.
This decision was based upon the illogical assumption that the Jews of Poland or Lithuania had equal rights to Palestine with the Arabs, who descend from the peoples that inhabited Canaan before the Israelitish invasion under Joshua. .It is noteworthy that the ancient Hebrew kingdom never was able to hold all Palestine, and that even in the heights of its prosperity and Solomonic glory, the richer coastal plain was owned and dominated by its more powerful neighbors. Now the case was to be reversed, and the Jews were to own that which historically they never possessed. The general belief that the present-day inhabitants of Palestine are Arabs, and therefore foreign to it, is erroneous. Palestinians of Arab descent are but few. Most Palestinians are descendants of the early Canaanite families and lived here long before the Israeitish invasion.
https://tinyurl.Com/CIA-Palestinians-r-indigenous