What is the significance of The Balfour Declaration from the book, Exodus?

The Balfour Declaration is a letter dated Nov. 2, 1917, written by the British Foreign Minister to Jewish philanthropist Lord Rothschild declaring his government is in favor of and will work for establishing in Palestine a national homeland for the Jewish people. It is written in the dark days of World War I when Britain has met disaster in Galipoli, Suez and Mesopotama. At the time, its Russian allies are beaten, and the promised Arab Revolt has not materialized.