In the larger scheme of things, Mel Gibson's drunken outburst against the Jews is very small potatoes. But it underlines an important element of anti-Semitism often overlooked. Contempt for the Jews is nearly always self-destructive, not necessarily in the short run, but over time, not simply person-to-person, but for nations, too. Anti-Semitism is for dummies.

British historian Paul Johnson documents how this works: Anti-Semitism clouds a person's judgment, forcing him to look for validation of his hatred, and this inevitably narrows his ability to reason. He's like the Marxist ever in search of "evidence" to confirm his economic theory, and voila, it's there. The anti-Semite can't accept what doesn't fit into his narrow worldview, and his hatred prevents him from enjoying the creativity of Jews, no matter that this creativity would pay him great dividends. Anti-Semitism dilutes the rewards of Jewish financial, scientific, artistic and intellectual strengths.

When Spain expelled the Jews (along with the Moors) at the end of the 15th century, for example, Spain lost the intellectual gifts it needed as the New World flowered with unprecedented opportunities for economic development. "The effect of official anti-Semitism was to deprive Spain (and its colonies) of a class already notable for the astute handling of finance," Paul Johnson writes in Commentary magazine. "As a consequence, the project of enlarging the New World's silver mines and [bringing] huge amounts of silver into Spain, far from leading to rational investment in a proto-industrial revolution or to the creation of modern financial services, had a profoundly deleterious impact, plunging the hitherto vigorous Spanish economy into inflation and long-term decline, and the government into repeated bankruptcy."

It's ironic that when Jews become financiers, they are often loathed for their abilities to manage money, and those in authority do not draw on their gifts. Spain never recovered from sending Jews into exile, and the Netherlands inherited good fortune when the Jewish refugees settled and contributed to the eventual mercantile and financial supremacy of that time. Amsterdam and Rotterdam became cities that endure as great trade centers to this day.

England expelled the Jews in the 13th century, but invited them back 300 years later, using money from the Rothschilds' international banking establishment to defeat Napoleon. Jews have flourished in England without religious restrictions, though Shakespeare tapped into the residue of official anti-Semitism in his portrait of Shylock in "The Merchant of Venice." (It's another irony that he probably never met a Jew.)

Laws that control and restrict Jews become models for control and restrictions of other religious and ethnic groups. Catherine the Great limited where Jews could live. Prejudice expanded to officially sanctioned pogroms that sent many Jews emigrating to the West. The Soviet Union enforced brutal legal restrictions on Jews and ruthlessly expanded them to other minorities. The Dreyfus case in France at the end of the 19th century provoked international condemnation and severely weakened the French military; its effects are felt today. Germany has yet to recover the talents of the Jews it killed or expelled under The Third Reich, including 20 Nobel Prize scientists.

The impact of anti-Semitism on the Arabs in the Middle East is only now getting the attention it deserves. Jews under the Ottoman Turks in the 15th and 16th centuries were welcomed for their advanced knowledge of spinning, weaving and dying of textiles. Their knowledge of European languages enabled Muslims to employ them as diplomats. Modern Islam merely blames them for everything they imagine going wrong.

Paul Johnson notes that Arabs have not only wasted trillions of dollars of oil revenues, blowing much of the money on armaments, but they have neither consolidated nor modernized their law nor copied any of the techniques of land management the Jews have used to make the desert bloom. Playing the victim and blaming the Jews for everything that goes wrong galvanizes hatred, but it doesn't do anything to make Arab life livable.

"The Protocols of the Learned Elders of Zion," the crude Czarist forgery that blames Jewish conspiracies for everything bad, is a perennial bestseller in the Arab world and taught as fact in the schools. The book, laughed at in the West, became a Cairo television series widely popular in the Islamic world.

Imagine how different things could have been if the Arabs had cooperated with Jews early in the 20th century. Imagine a Jewish-Arab collaboration to build real schools, teaching hospitals and great universities. Imagine what might have been if they had worked the land together, exchanging techniques of cultivation. Imagine what might have been if they had cooperated to develop joint social services for the needy of both peoples. Imagine.