November 2 marks the 102nd anniversary of the Balfour Declaration, about which I have previously written at length in Mosaic. There, I focused on how the actors who brought the declaration into being assured it would have international legitimacy, and on the tragic failure of Britain and the international community to keep their promise to the Jewish people in the aftermath. Here I want to reflect on an overlooked rationale proposed by the Zionist leader Chaim Weizmann to give the declaration some staying power after the world war would finally end.

Historians have long been preoccupied by this question: why did the war cabinet of Prime Minister David Lloyd George issue the November 2, 1917 declaration in the first place? After all, it seemed so improbable, both at the time and in retrospect. That sense of improbability was well expressed by the Hungarian Jewish writer Arthur Koestler, who called the declaration “an act dangerously outside the cautious routine of diplomacy. The whole thing was unorthodox, unpolitic, freakish.” Given that impression, the document quickly invited obsessive speculation as to the real motives behind it, and initially the speculation ranged very widely.

The guesswork would subside when Britain opened its archives in the 1970s. We now know that, far from being “unpolitic,” the Balfour Declaration was very politic indeed. The bottom line was this: the British war cabinet thought a declaration supporting a Jewish national home in Palestine would make for good propaganda among the Jews of Russia and America, who had been tepid in their support of the Allies in a war that had been dragging on for three long years. The Jews, so the reasoning went, would be fired by the prospect of a Jewish Zion, and would use their influence to keep Russia firmly in the fight and persuade the United States to step up.

The war cabinet also thought that official British sponsorship of Zionism would give England an edge over France in the inevitable postwar wrangle over the disposition of the territories of the Middle East. By assuming the noble burden of helping the Jews, Britain would extricate itself from its promise to share Palestine with France as stipulated in the 1916 Sykes-Picot agreement—a deal that Lloyd George wanted to break for reasons of postwar imperial strategy.

To summarize: the Balfour episode was a matter of realpolitik all along. True, some have argued with surface plausibility that both Lloyd George and foreign minister Arthur Lord Balfour were motivated at least in part by religious sentiment. That they held such sentiments is not in doubt; but no evidence of this shows up in the cabinet papers themselves. Rather, British officials debated Palestine as they debated India or Egypt, that is, as an element in their thinking about how best to preserve and, if possible, expand the presence of the British empire on the world map.

Indeed, Zionist leaders, and above all Chaim Weizmann, chief lobbyist for the declaration, understood these British motives perfectly well. Weizmann also knew something else: once the guns were to fall silent in Europe and the Middle East, and once Britain had Palestine firmly in its pocket, the particular wartime needs that prompted the declaration would vanish. What, then, would persuade Britain to honor its vague wartime promises?

To that question, Weizmann also had an answer: in his words, the “Jewish problem.” He offered it even while promoting the declaration, but emphasized it much more in its aftermath.

Some historians of the declaration are oblivious of any such problem. Consider, for example, the Oxford historian Avi Shlaim, who has repeatedly made this statement:

At the time [of the Balfour Declaration], the Jews constituted 10 percent of the population of Palestine: 60,000 Jews and 600,000 Arabs. Yet Britain chose to recognize the right to national self-determination of the tiny minority and to flatly deny it to the undisputed majority.

Actually, “national self-determination” doesn’t appear in the Balfour Declaration, which promised instead to advance “in Palestine a national home for the Jewish people.” But the wording of that phrase was no small point. Palestine was to be a “national home” not only for the 60,000 Jews already there but for the “Jewish people”—that is, the Jewish people in its entirety.

That people and its “problem” were large ones. Ever since the Holocaust, we have come to think of the Jews as a relatively small people, but at the time there were as many Jews in the world—twelve million—as there were Egyptians in Egypt. Of these twelve million, more than five million were located in the Russia empire alone (including Poland). That meant there were as many or more Jews in Russia as, for example, Irish in Ireland, Greeks in Greece, Argentines in Argentina, and Australians in Australia. The Jews of Russia outnumbered the Arabs of Palestine, Transjordan, Syria, and Lebanon combined.

To anyone thinking postwar thoughts, these Jews posed a substantial problem indeed. The problem was that it seemed likely they might begin to move.

Again, the massive number of Jewish lives taken in the Holocaust has tended to make us forget just how devastating World War I had already been for European Jews, and especially those of the Russian empire. The front lines in the east, between Germany and Austria on the one side and Russia, a member of the Allied powers, on the other, swept back and forth through the Pale of Jewish Settlement like a threshing machine.

Thousands of Jews perished as “collateral damage” or in deliberately planned atrocities. Hundreds of thousands lost their homes and became wanderers on the roadsides and in the train depots. The Russian army deported 600,000 in boxcars to the east. As Weizmann put the demographic facts in 1916,

[I]t is already obvious that [the war] will deal a shattering blow at what has been for centuries the great reservoir of Jewish strength. . . . The havoc brought by the war to the Jews of Poland has been compared to the destruction of Jerusalem by the Romans, and the comparison is by no means fanciful.

In drawing this arresting analogy, Weizmann meant to say that the Jews were about to be dispersed once again. If so, this would be a movement of millions. Since the early 1880s, two million had already left the Russian empire, mainly for America but also for England, where large numbers were concentrated in the East End of London. Domestic sentiment against them was rising, and doors were beginning to close. Balfour himself, during an earlier stint as prime minister, had tried to shut Britain’s gates altogether through the Aliens Act of 1905.

Who would take another million? Or two? Or four? No country, Weizmann claimed, could absorb such numbers—except Palestine. But could it, really? Where was the evidence?

This very question first came up in the week prior to the decisive cabinet meeting on whether to issue the Balfour Declaration. It was prompted by Lord Curzon, former viceroy of India, once described as “the most traveled man who ever sat in a British cabinet.”

Curzon had visited Palestine in 1882, and 35 years later remembered it as “a tiny country which has lost its fertility and only supports meager herds of sheep and goats with the occasional terraced plot of cultivation.” This remote recollection moved him, in late October 1917, to address a memo to the war cabinet entitled “The Future of Palestine.” He painted a grim picture; Palestine, he pronounced, “was incapacitated by physical and other conditions from ever becoming in any real sense the national home of the Jewish people.” After all, its territory was comparable in size to that of Wales, and Wales “supports a population of only two million.” So constricted and impoverished a land “will not in my judgment provide either a national, a material, or even a spiritual home for any more than a very small section of the Jewish people.”

The unspoken conclusion: Palestine couldn’t possibly solve the Jewish problem, and for Britain to issue grand unfulfillable promises to the contrary would be an act not of practical politics but of romantic folly.

The burden of challenging the formidable Lord Curzon fell to the much younger Sir Mark Sykes, an adviser to the cabinet, a celebrated traveler in his own right, a convert to Zionism, and in many ways an unsung hero of the Balfour Declaration. It was Sykes who had instructed Weizmann (and Naḥum Sokolow) on how best to maneuver. Generally, he let the Zionists make their own case since they did it extraordinarily well, but against Curzon he had to act himself, since he alone could claim to know Palestine better.

In the course of a few pages, Sykes’s counter-memo, written four days later, demonstrated in detail his superior familiarity with the country—its climate, its agricultural produce, its existing settlements. “Having known Palestine since 1886,” he stated, “I am of [the] opinion that if the population is now 700,000, [and] granted security, roads, and a modest railway accommodation, it is capable of being doubled in seven years . . . and with energy and expenditure it would be quadrupled and quintupled within 40 years.”

In brief, Sykes was arguing for a figure within four decades of upward of three million Jews, achieved at the brisk pace of almost 100,000 immigrants a year. His own unspoken conclusion: Palestine could go very far indeed toward alleviating the Jewish problem.

It would be a mistake to think that the final cabinet decision hinged on this debate alone. As I’ve stressed, the case for the declaration was decided by Britain’s political calculations at the time. Besides, by the end of October 1917 Balfour and Sykes had gathered the support they needed, not just in the cabinet but also from Britain’s allies.

But a year later, with the war ended, the declaration, still not fleshed out in practice, would be shorn of its prior rationale. To get it “ratified” internationally, another urgent case needed to be made and pressed forward strongly: namely, that only the Jewish “national home,” on as large a territory as possible, had a chance of solving the Jewish problem. Moreover, absent such a solution, the repercussions would fall not only on Jews.

Weizmann knew how to build on Gentile admiration of the Jews. He also knew that admiration often went together with fear. The larger the Jewish problem were to loom, the greater would be the appeal of the Zionist solution. Thanks to Sykes, who in deflating Curzon had rendered a crucial service to the Zionists, Weizmann could now speak of big numbers with less worry of contradiction. By talking small he would receive little—so he talked very large indeed.

Here is Weizmann in late 1918 exercising foresight and warning Balfour that “when things settle down a little after this war, Jewish emigration [from Russia] will assume formidable proportions.” Indeed, he anticipated that “countries which have hitherto admitted considerable numbers of Jewish refugees may make any further influx of such refugees very difficult.” (Balfour, Weizmann would note afterward, “concurred in this view.”)

With Palestine the only solution, Weizmann now floated a stupendous figure: “We should be able to settle in Palestine about four to five million Jews within a generation, and so make Palestine a Jewish country.” This was the same figure he would cite at the Paris peace conference in 1919. His message: give us a wide Palestine, in expansive borders, and we will solve our Jewish problem—and yours. Otherwise, as he put it to Balfour, desperate and homeless Jews might overturn the world:

If the Jews do not obtain a satisfactory settlement this time, they will be driven to despair. . . . I would go further and say now that the world will never have peace until the Jewish problem is solved in a satisfactory manner.

Weizmann made the threat loom still more ominously in his presentation to the Paris Peace Conference. The flow of Jews from Russia, already 250,000 annually before the war, “will increase still further,” he warned.

We see here a picture of hundreds of thousands of Jews wandering from the countries where they will no longer be able to find the means of existence towards those which might procure it for them but where they will not be received. This is a very serious problem. . . . [Palestine] is the sole solution which can give to the Jews peace between themselves and the rest of the world. It is the only one which can permit their energy, rather than being dissipated and transformed into bitterness and violence, as happens with those who feel themselves in conflict with the milieu surrounding them, to be creatively employed at last.

To the warning that the Jews would be numerous and wandering, Weizmann thus added a third peril: they would be violent, too.

By 1922, when the Balfour Declaration became incorporated in the preamble to the mandate over Palestine issued to Great Britain by the League of Nations, its rationale had been transformed from a wartime expedient to a peacetime necessity.

But here we come to the tragedy of the Balfour Declaration.

In the 1920s, Weizmann and his colleagues would come up against the harsh realities of economics. The yishuv, the Jewish community in Palestine, lacked a broad enough base to absorb millions of Jews. Young, able-bodied pioneers were encouraged to come, and so were moneyed entrepreneurs. Others, however, were not welcomed, as they would have constituted a burden.

But neither were Jews lining up to volunteer. In the lands of the former Russian empire, the situation had improved. True, horrific pogroms occurred during the Russian civil war of 1919; perhaps 50,000 Jews perished. But the regime established by the Russian revolution officially gave Jews equal rights and national standing. For most, this represented hope enough. In Poland, for its part, a new republic promised minority rights, and for a brief moment there was hope there, too.

All that would change with the rise of Hitler in 1933 and the spread of anti-Semitic persecution across Europe. But by then the doors of Palestine itself were closing, and the British had begun to renege on their Balfour promise. In 1937, a partition plan between the Arabs and the Jews was proposed by the royal Peel Commission. The part of Palestine allotted to the Jews shrank dramatically to little more than a narrow coastal strip. Weizmann was pressed by the commission for an estimate: did he still mean to bring half of the Jewish people, six million, to Palestine? His aching, despondent answer:

No. I am acquainted with the laws of physics and chemistry, and know the force of material factors. In our generation I divide the figure by three: two millions of youth, with their lives [still] before them. Two millions and perhaps fewer: sh’eyrit ha-p’leytah—only a remnant shall survive. We have to accept it.

Ultimately, even those two million would perish, leaving only a few hundred thousand to be collected from the ashes. The Jewish population of independent Israel reached the two-million mark only in 1962.

An unmitigated tragedy, then? Weizmann would not have thought so. He put it like this: “If the question of the Jewish refugee gives a new spur to the Zionist effort, it is not and never was the primal motive. . . . Zionism envisages more than the negative relief of suffering.” Zionism was to be judged not by the quantity of lives saved (over which it had little say in any case), but by the quality of the sovereign Jewish life that Zionism would foster.

By 1918, the great powers imagined that the Jewish national home of the Balfour Declaration might solve Europe’s quantitative Jewish problem. It didn’t: only 400,000 Jews entered Palestine during the British mandate period, while the millions met with extermination in the Nazi “final solution.” Yet the declaration did clearly mark the beginning of the end of the Jewish problem as Weizmann and the Zionists understood it: a total absence of power that left the Jews as wanderers, vulnerable and weak.

Over the past century, the people of Israel have diligently built the power needed to forge their own solutions, mastering their fate as never before. In 1917, Lord Balfour and the British government made a promise on behalf of the Allies. In 1939, Britain unilaterally abrogated it. In 1948, Israel finally kept it, as it has done ever since.