Why?? The 1939 white papers is a British official document which offer a complete & clear illustration for Balfour declaration Vague wording. Yet it is not the only one. Following San Remo conference which applied the mandate in April 1922 , UK issued on July 1922 a white paper related to Balfour declaration & its meaning. Here it states :-
http://avalon.law.yale.edu/20th_century/brwh1922.asp
So UK clearly denies that Balfour declaration was mean t to establish a Jewish state in Palestine. In more decisive paragraph, the 1922 white paper denies any other nationality for Palestine Jews than Palestinians.
In other words, Balfour declaration had never called for a Jews state over part or all of Palestine. Jews are encouraged to develop their community as an integral part of Palestine. These Jews shall be regraded as Palestinians with equal rights to the Arab Palestinians.
The 1939 white papers are no different to the 1922 white papers. Again UK government assures that Balfour declaration vague wording of the Jews national home does not mean a state for the Jews.
http://en.wikipedia.org/wiki/White_Paper_of_1939
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