For more than three months, the Libyan town of Misrata has been under siege, and its citizens are being bombarded by Muammar Gaddafi’s well-equipped army and air force. Nobody knows the number of civilian casualties, but over a month ago, the Guardian reported that there were over 1,000 dead and 3,000 wounded.Misrata is only a short distance from the Tunisian border, where a popular revolution installed a non-tyrant government. And yet, Tunis does not extend any help to its beleaguered Arab brethren in Misrata, except for accepting the Libyan refugees fleeing the war.The fate of Benghazi, located closer to the Egyptian border, could have been much worse: Were it not for a last-minute rescue by the NATO air-force, the people would have been slaughtered en masse when the armed columns of Gaddafi began their avenging march to the city. A few days before that intervention, the Guardian reported the frustration of a local engineer, who waved his clenched fist at the sky and shouted: “Where is [an] aerial counter-blow? Where is the West? They must stop Qaddafi before we all die.” He did not address his outcry to neighboring Egypt, which, with its huge army and air force, could have saved the people of Benghazi.The only Arab states rendering any help to the Libyan people are Qatar, Jordan and the Emirates, and they confine themselves to aerial humanitarian assistance. Nothing is being done by any Arab organization to save the rebels from annihilation.Now, let’s imagine a hypothetical scenario in which two Jewish communities face similar dangers, and right across the border, there exist two Jewish states. Can anyone even imagine a situation in which these Jewish states would turn a blind eye to their menaced brethren? Is it at all conceivable that these states would not mobilize their armies to save the lives of the besieged Jews? Even without a state of their own, Jews in the Diaspora have always mobilized to help endangered Jewish communities. Indeed, Jewish solidarity – from the Joint to Col. Marcus’s volunteers in the War of Independence – has become legendary. But where is the Arab Col. Marcus? Where is the financial assistance from oil-rich governments that could help the people of Misrata? If solidarity and loyalty are the hallmark of a people, then the Jews are certainly a people. And yet, anti-Israeli university professors in Israel, who thrive on Jewish donations, deny the existence of such a people. This is the edict of the latest academic fashion, and Prof. Shlomo Sand of Tel Aviv University is its main trendsetter. In his book The Invention of the Jewish People, Sand claims that the Jews were not expelled from ancient Palestine, that those who remained there were the ancestors of today’s Palestinians, that the Ashkenazi Jews are the descendents of the mass conversion of Khazars – a seminomadic Turkic people – to Judaism over 1,000 years ago and, needless to say, have no historical claim over Palestine.Naturally the book drew worldwide attention, won an important French prize and was widely covered by the international media. Here was the ultimate attack on Israel: If there is no Jewish people, there should be no Jewish state, and strictly speaking, there should be no Jewish history (although Sand is ready, so it seems, to grant recognition to the Israeli-Jewish community).IS THERE any scientific basis to Sand’s allegations? And if there is, what are its political ramifications? The answer is twofold: There is no evidence whatsoever for these statements, and even if they are true, they have no significance.Let us take his claim that Ashkenazi Jews are descendents of Khazar converts. There is no evidence for this (although it is quite possible that a minority stems from such alleged conversions).A wide range of reliable genetic tests have negated this tale, there are no Khazar words in Yiddish, and if we assume that the Ashkenazi community is of Khazar extraction, we must also assume that many of them decided, by acquiring names such as Cohen and Levy, to retroactively serve the Jewish God as holy men in a Jewish Temple destroyed almost 1,000 years before their conversion.But let us assume that there was mass conversion and that most or all Ashkenazi Jews are of non-Jewish extraction. Since when are converts not considered Jewish? According to both Halacha and liberal principles, a convert to Judaism is a Jew for every purpose, including his yearning for Zion. According to the book’s argument, King David himself, whose grandmother was a convert, is not Jewish and has no claim to Zion.The truth is that Sand’s compilation of rubbish serves an important purpose. It is a further erosion of the line between academic writing and its parody. Thus, Sand makes fun of all the genetic studies, undertaken by firstrate scientists, that prove two astounding conclusions: Ashkenazi Jews are genetically closer to oriental Jews and oriental non-Jews than to the non-Jewish European host societies, and Jews managed to keep their separate genetic identity throughout this long and eventful time.Needless to say, no nation is, or should be, racially pure. Jews did intermarry, and conversions took place. Evelyn Waugh, in a letter to Nancy Mitford, notedices the diversity of ethnicities among Jews when he visited Palestine in the ’30s. Herzl was aware of this diversity and remarked that “no people are homogenous racially.” Meanwhile, all French children, including African-French, learn in school about “our ancestors, the Gauls”; are they different from the alleged descendants of a convert who prays, “Next year in Jerusalem?”What Jews posses that is conspicuously absent among their Arab cousins is solidarity in time of need.And it is this Jewish solidarity, among other things, that has enabled Israel and its universities to survive.The writer is a professor of law at the Interdisciplinary Center Herzliya, a former minister of education and Knesset member, and the recipient of the 2006 Israel Prize in Law (www.amnonrubinstein.org).