Oh, but he did. The Balfor declaration would not have happened had he not influenced the decision makers.
I haven’t heard about his interaction in getting the Balfour Declaration included in the League of Nations Palestine Mandate. I know that the British Government insisted on including it in the legal papers. Even so, let’s just say for sake of discussion that he did have a part in that ... but ... in spite of that, “everything went downhill” after that, as the British government continually worked, in all the years after that ... to undo anything and everything the Balfour Declaration said and stood for!