In the coming weeks, numerous Jewish organizations and institutions will celebrate the 100th anniversary of the Balfour Declaration and the 50th anniversary of the United Nations partition plan for Palestine.Remarkably, however, the proposals that will be celebrated were just that – proposals. Neither of them actually was implemented, at least not in the way their authors intended.The Balfour Declaration, issued in the form of a letter from the British foreign minister on November 2, 1917, endorsed “the establishment in Palestine of a national home for the Jewish people” and pledged to “use [Great Britain’s] best endeavors to facilitate the achievement of this object.”Zionist leader Chaim Weizmann said he “heard the steps of the Messiah” in Balfour’s proclamation.For a short time, the British Mandate authorities opened Palestine’s doors to Jewish immigration and permitted Jews to purchase land without restrictions. But when Palestinian Arabs began to riot, British policy began to change.Each new wave of Arab terrorism in the 1920s and 1930s resulted in new limits on the development of the Jewish national home. The 1939 White Paper reduced Jewish immigration to a trickle, and the 1940 Land Transfer Regulations allowed unrestricted Jewish land purchases in just 5% of the country. At protest rallies throughout the country, the new regulations were compared to laws in Nazi Germany that likewise prohibited Jews from owning land.Instead of “facilitating” Jewish statehood as Balfour had pledged, the British were now blocking it. If a Jewish state were to come into being, it would be despite British obstruction of the Balfour Declaration. The plan adopted in 1947 by the United Nations likewise was never implemented. The UN proposed to create separate Jewish and Arab states in western Palestine. (The eastern 78% of the country already had been severed by the British many years earlier, and renamed Transjordan.) The Zionist leadership accepted the UN proposal, but both the Palestinian Arabs and neighboring Arab regimes rejected it.As Arab armies mobilized and the Arab League’s secretary-general vowed to carry out “a war of extermination and momentous massacre” of the Jews, the UN stood idly by. Its member-states were not willing to send soldiers to enforce partition.So why all the celebrating next month? Mostly because the two documents conveyed a certain legitimacy. The Balfour Declaration represented the endorsement of Jewish statehood by the world’s greatest power. The adoption of the partition plan by the UN General Assembly meant the idea of a Jewish state was supported by the majority of the international community.For a people who had been persecuted and relegated to national homelessness for close to 2,000 years, these developments offered the psychological comfort that Jewish isolation might soon be coming to an end.But when it came to the Jewish people’s most urgent practical need – a state of their own – the failure of both the British and the United Nations to implement what they promised illustrated the gap between rhetoric and reality.In the end, the Jews would have to fight for what was theirs. They did fight, and they won. Next year’s 70th anniversary of the establishment of Israel will provide an opportunity to celebrate what was achieved, rather than merely what was promised.The writer is the author or editor of 17 books about Jewish history and Zionism, including ‘The Historical Dictionary of Zionism’ [coauthored with Chaim I. Waxman].