I have become Ariel Sharon. I don't know when it happened exactly, though it was some time after I moved to Europe last year. Maybe it was in Brussels, or London, or Madrid, or perhaps at one of the antiwar rallies, or in a café talking with friends.

The Jews, I hear people say, oppress Palestinians and control American foreign policy. "The Jews". I am them, they are me. Having grown up in a secular Jewish family thousands of miles away in Los Angeles, I never expected to become a symbol of my people. In fact, when I was a boy being Jewish didn't mean that much. It was just another ethnic background in the mix of my friends; European Christians, Latinos, Chinese, African-Americans, Sikhs and even one who was half-Japanese half-Jewish. We rode skateboards, hung out at the beach and the shopping mall and tried to dress like pop stars. When I thought about it, I associated Jewishness with being brainy, like Einstein, or neurotic, like Woody Allen. As a ten-year-old I was thrilled to discover that the creators of Superman were Jewish. For my bar mitzvah I received a book called Great Jewish Sports Stars. It was a thin book, but interesting. Rock and roll seemed a lost hope, until I found out Bob Dylan was Jewish, as was David Lee Roth, the lead singer of Van Halen. These were the musings of a teenager trying to find a place in the world, most of which faded when pimples and girls came along.

Now, in Europe and grown up, I find myself baffled when I am asked about what I am told is the "Jewish lobby" in America, which controls US foreign policy while at the same time promoting "Jewish business interests". Some weeks ago a veteran British journalist informed me that she had decoded my Jewishness from my last name, and asked: "Don't the Jews control the media in the United States? After all, that must be why the Bush Administration supports Israel." How did it happen that Europeans, who always claim that Americans have no historical memory, have slipped so easily into such stunningly lazy and historically arrogant rhetoric? For many Europeans, the Israeli-Palestinian conflict is an abstraction, a symbolic fight of good versus evil: "Jewish oppressors, Palestinian freedom fighters." There are no people.

Criticism of the Sharon Government's often brutal policies is absolutely legitimate, and is a feeling that I and millions of Jews in America and Israel share. Israel is a democracy, just like the United States and every country in Europe, and it has a right wing, a left wing and a large majority in the middle that for decades has supported a peace agreement with the Palestinians.

The PLO conceded Israel's right to exist in 1998, but here in Europe progressive liberals have taken up the language of the fringe right wing, and many still question why there should even be a Jewish state.

The two political wings are drawing deeply from the same foul source. "Anti-Semitic prejudice is alive and well," said Romano Prodi, the President of the European Commission, last month. "We can clearly see vestiges of a historical anti-Semitism which was once diffuse throughout Europe."

In this mutated anti-Semitism, ostensible concern for the underdog Palestinians becomes a chance to score points against the Bush Administration. As the argument runs: the Israelis and their Jewish backers in the US use the Holocaust as a rationale for a barbaric land grab. The US may even have invaded Iraq at the behest of Israel. This kind of sloppy sloganeering, that appears regularly at anti-war rallies, among intellectuals and in otherwise erudite journals, undermines legitimate criticism of the Bush-Sharon alliance. It is now de rigueur for European commentators to dismiss concerns about anti-Semitism as merely a cover by Jews to blunt criticism of the Sharon Government.

Earlier this month The Economist magazine held a debate addressing the question: "Are opponents of anti-Semitism the new McCarthyites?" Talking about anti-Semitic rhetoric is not the same as saying another Holocaust is imminent. At the same time the atmosphere in Europe has grown increasing ugly, with attacks against rabbis, the firebombing of synagogues and the defacing of cemeteries. These attacks are generally blamed on disenfranchised Muslim youth here who, since the 2000 intifada, have scapegoated Jews.

Defying the stereotype: a Jewish activist offers a soldier a rose of peace This is a variation of the old anti-Semitism, one that I saw in Hungary in 1999, at a rally of 50,000 people in the centre of Budapest, some of them displaying swastikas and even wearing SS uniforms. As scary as it was, this was clearly an anachronism. In the two years I spent in Eastern Europe I never heard the rhetoric that is now common in what was once called liberal Western Europe.

In the sloppy thinking of the new anti-Semitism, a battle of good versus evil is waged like that in the Lord of the Rings movies, with Palestinians the defenceless Hobbits and Israelis the Orcs. Nobody much cares when the Orcs are killed. And Europe is somehow an innocent bystander. Thus, the European Monitoring Group, a human rights arm of the European Union, decided not to release a report on the rise in anti-Semitic attacks after it determined that the violence was perpetrated by Muslims.

European intellectuals have taken up the double standard as well. They evidently thought they were being moral when 120 university professors from 13 European countries called for a boycott of visits from Israeli academics; the same probably goes for the Oxford dons who banned Israeli researchers from laboratories.

It is hard to imagine anybody taking these sanctions against professors from Turkey for their government's treatment of the Kurds, against Russians for Chechnya, Chinese for Tibet, or the British for Northern Ireland. Europe has gone tone deaf.

It apparently needs to be said that when discussing political actors there is no such thing as "the Jews", any more than Christians or Muslims constitute a single group. Yes, right-wing Jewish groups in the United States aggressively lobby to support the Sharon Government and the fanatical Jewish settlers. They are joined in their efforts by Christian evangelical groups, the hardcore base of the Republican Party that numbers in the tens of millions.

Yet I haven't heard any Europeans attacking the Christian Far Right lately. The real flux of politics is seemingly completely absent from the European view. Clinton was immensely popular with American Jews, who are traditionally liberals, yet it was he who pushed the Israeli Government harder than any other modern president.

President Bush, who garnered less than 20 per cent of the Jewish vote in 2000, has given the Sharon Government run free rein. The new anti-Semitism is about language. Language is definition, and definition is the first step before action. Jews define themselves as people who believe in God and follow the Torah, or at least whose ancestors did that.

That's it. The problem starts when people start assigning them traits, motivations and, in the special case of anti-Semitism, some kind of secret power and influence that is far greater than their small numbers. If the definition of the Israeli-Palestinian conflict is "Jewish and American colonialism" then there is no solution. Thinking such as this probably explains why a British friend of mine recently said: "I wish Israel didn't exist." Something is wrong if in attempting to support the Palestinians you dehumanise Israelis as functionaries of some Jewish and American conspiracy.

A nine-year-old boy who is killed in the West Bank by errant Israeli machinegun fire is no more or less a martyr than a nine-year-old boy in Jerusalem blown up by a suicide bomber on the way to school. Innocents are killed or maimed almost every day in this horrifying conflict, and it is wonderful that Europeans are so engaged and politically active. Yet nobody has ever said to me: "You are Jewish? Oh, I am sorry that 17 innocent schoolchildren were killed today in a bus bomb attack."