Last month's bloody encounter on a ship off Gaza offered deadly proof of the adage: "Those who cannot remember the past are condemned to repeat it."

Israelis above all others should have recalled that aphorism, which was coined by the philosopher George Santayana. Six decades ago, Zionist freedom fighters attempted to run a blockade of the Holy Land's coast maintained by the British, setting off a lethal confrontation that turned world opinion in favor of the establishment of a Jewish homeland.

Now, the storming of the Turkish aid ship the Mavi Marmara has played into the hands of hostile regimes and leftist ideologues seeking to delegitimize Israel — not just criticizing a particular Israeli regime, but arguing that the very idea of a Jewish state was an unfortunate error.

It will do Israel and her supporters little good to protest that some aboard that aid flotilla were spoiling for a fight, not singing, "All we are saying is give peace a chance." Video footage shows some of the blockade-runners shouting "Khaybar! Khaybar!" — a seventh century battle when Prophet Muhammad's followers killed Jews, exiling survivors from Arabia. Other clips show Israeli commandoes being attacked with clubs.

But fine-tuning the encounter won't help. Human beings need to simplify. We're desperate to know who are the good guys and who are the bad. Symbolism trumps complexity. To understand the strength of that impulse, consider that nobody is picketing Egyptian embassies. Yet moral logic dictates this should be true. Egypt has been Israel's partner in cutting off the people of Gaza from the outside world.

The unavoidable fact is that Israel has virtually handed its head on a platter to its enemies. The British made a similarly fateful error in 1947.

At the time, two years after World War II ended, myriad Holocaust survivors were stuck in displaced-persons camps in Europe. The horrors of Auschwitz and Treblinka had convinced them of the Zionist argument that Jews needed the protection of a homeland. Besides, no country, including the United States, welcomed Jewish refugees.

Great Britain was determined to hold the lid on Jewish immigration to the Holy Land, then under British colonial rule. They were in a bind, having made incompatible promises about Palestine to both Arabs and Jews. British warships maintained a blockade in the eastern Mediterranean. Determined to break through — and to demonstrate the plight of Holocaust survivors — a Zionist organization bought an aged passenger ship that lately had seen duty during World War II. Renamed "Exodus 1947," an echo of the ancient Jews' escape from Egypt, it took aboard 4,515 passengers on July 11, 1947. A week later, the Royal Navy boarded it a few miles off the Palestinian shore. The passengers fought back, and in the encounter two passengers and a crew member of the Exodus were killed.

Others were taken by the British to the port of Haifa, in the land of their dreams, then herded aboard British ships and sent back to whence they came. At that very moment the United Nations had a fact-finding commission in Palestine. It took reams of testimony from Arabs and Jews. The arguments the U.N.'s representatives heard then are much the same as those of pro-Palestinian and pro-Israeli voices now. The Arabs said that since the Holocaust was not of their making, why should they bear the burden of resettling its survivors. Jews said that Israel was the land of their ancestors, which they had been forced to leave by the Romans.

In the middle of that point-counterpoint argumentation, members of the U.N. commission witnessed the brief landing and deportation of the Exodus' passengers, a sight more powerful than any legalistic testimony. The episode's aftershocks continued when the British brought their Jewish captives to internment in Germany, whose leaders had plotted the destruction of world Jewry.

Sympathy swung in favor of a Jewish state, and later in 1947 the U.N. voted to divide British Palestine between Arabs and Jews.

Now Israel faces a dilemma the British once did. Images of those killed on the Mavi Marmara have become symbols of a cause, just like those who perished on the Exodus. They will wash out any consciousness of the complexity of the Israeli-Palestinian struggle like the fact that Israel offered peace at least five times; each time the Palestinians declined. Just as many Jews have been exiled from Arab countries as Arabs were exiled from Israel.

Long ago, Golda Meir, who later on became Israel's prime minister, lectured the British not to underestimate the Jewish resolve to fight for independence. Having lost a war of words in the clash off Gaza, Israelis might want to try the following mental exercise: Think of Meir's words as if they were a message from the Palestinians, delivered by a flotilla of their supporters.

"It's an illusion," she said, "to believe us weak."