To wit: Upon the closure to WW1 and with the defeat of the Ottoman Empire: In 1919, the US Woodrow Wilson Administration King-Crane Commission advised: “a national home for the Jewish people” is not equivalent to making Palestine into a Jewish State; nor can the erection of such a Jewish State be accomplished without the gravest trespass upon the “civil and religious rights of existing non-Jewish communities in Palestine”
On Sept. 22, 1947, the US Department of State’s ‘Middle East Office’ Loy Henderson strongly warned Secretary of State George C. Marshall that partition of Palestine into Arab and Jewish states was not workable and would lead to untold troubles in the future. (Henderson informed Marshall that his views were shared by “nearly every member of the Foreign Service or of the department who has worked to any appreciable extent on Near Eastern problems.”)
Although the US State Department/Department of State reflected Henderson’s anti-partition views, Harry Truman’s White House was supporting partition because of strong domestic US political pressure. (Truman was so unpopular at the time that there was speculation he might not be able to win the Democratic Party’s nomination, much less the presidential race.)