In his new book Never Again?, Abraham Foxman, national director of the Anti–Defamation League, makes an extraordinary claim. "I am convinced," he writes, that "we currently face as great a threat to the safety and security of the Jewish people as the one we faced in the 1930s – if not a greater one." This view was echoed by the Chief Rabbi of the United Synagogue, Jonathan Sacks, who wrote recently that "anti–Semitism now exists in more virulent forms than at any time since the Holocaust." In April 2002, the front page of the Independent showed a picture of a desecrated synagogue in North London accompanied by the headline: "A picture that tells a shocking story: the rise of anti–Semitism in Britain." The situation is apparently so serious that Washington Post columnist Charles Krauthammer was led to conclude that "in Europe, it is not very safe to be a Jew."

The notion that current levels of anti–Semitism rival those of the 1930s may appear absurd, but there is evidence to show that anti–Semitic attacks and abuse have risen in recent years. Michael Whine, director of a monitoring organisation called the Community Security Trust, wrote in a recent collection of essays entitled A New Anti–Semitism? that the number of anti–Semitic incidents in Britain, including physical and verbal abuse and attacks on synagogues, averaged 282 per year between the mid 1980s and 1999. That number rose sharply to 405 in 2000, 310 in 2001, 350 in 2002 and 375 in 2003. A series of recent polls have revealed a disturbing presence of anti–Semitism in Europe: in January, for example, an Italian poll revealed that nearly 18 per cent of those questioned, from nine European countries including Britain, said they felt Judaism was 'intolerant', and that nearly 17 per cent did not consider Jews 'real' compatriots. In November of last year, two synagogues in Istanbul were truck–bombed during Sabbath services, while an Orthodox Jewish school in a Paris suburb was almost destroyed by arson. Attacks on Jews on the continent have increased in recent years, particularly in France and Eastern Europe, with synagogues desecrated and Jews attacked by gangs in the street.

If the degree of anti–Semitism has increased alarmingly in Europe, what about its character? What makes it 'new'? If, in the past, anti–Semitic violence has generally come from the far right, it is now thought to come increasingly from Muslim extremists and Palestinian radicals. The recent anti–Semitic attacks on the continent have occurred predominantly in countries with large Arab populations, and those who perpetrated the Istanbul synagogue bombings were suspected of links with Al–Qaida. Crucially, the peaks in anti–Semitic activity clearly correlate with events in the Middle East: the Al–Aqsa Intifada which began in September 2000 and the Israeli army's reoccupation of West Bank towns in April 2002.

While violence against Jews is never a justifiable response to political injustice, it is important to recognise a link between Israeli policies and the occurrence of these attacks. Hostility towards Israel in the Arab world is articulated in virulently anti–Semitic terms: the Protocols of the Elders of Zion circulates widely in the Arab world and is the inspiration for a long–running Egyptian television series. And yet, Israel is often referred to by hardliners in the Arab world as the 'crusader state', symbolically a Christian, not Jewish, entity. Citing Bernard Lewis, Anthony Lerman has argued that post–war anti–Semitism is not an indigenous product of the Middle East, but was imported from Nazi Germany and invoked for a political end. Although the hatred of Jews may not, therefore, be the primary motivation for extremists in the Middle East, the anti–Semitic rhetoric they use is highly vitriolic. However, this is not the primary object of attack in many accounts of 'a new anti–Semitism'.

Rather, the majority of the polemic in these books and articles is directed against a form of anti–Semitism originating in Europe, specifically Britain. This may appear odd, since the British Jewish community is one of the best established and least persecuted in Europe. But Britain also has a thriving and robust journalistic culture, and it is the media which emerges as the focus of criticism.

The careful analysis of apparent manifestations of anti–Semitism in the British press forms the basis for many claims of a 'new anti–Semitism', and there are certainly grounds for complaint. The New Statesman cover which featured a gold Star of David piercing a Union Jack, headlined by the words 'A Kosher Conspiracy?' evoked the Nazi slur that Jews threatened national interests. A cartoon in the Independent which portrayed Ariel Sharon biting off the head of a Palestinian child reminded many readers of the medieval stereotype of Jews murdering Christian children. Despite the outcry it prompted, the Political Cartoon Society named it Cartoon of the Year for 2003. Emanuele Ottolenghi, a Fellow in Israel Studies at Oxford, was correct when he wrote in the Guardian in November last year that Israel's critics should not repeat traditional anti–Semitic themes under the anti–Israel banner:

"When such themes — the Jewish conspiracy to rule the world, linking Jews with money and media, the hooked–nose stingy Jew, the blood libel, disparaging use of Jewish symbols, or traditional Christian anti–Jewish imagery — are used to describe Israel's actions, concern should be voiced."

Even though examples of anti–Semitism can be found in the European media, it is wrong to conflate these, as proponents of the argument tend to do, with anti–Semitic violence in the Middle East. "The American and European Left" according to American writer Phyllis Chesler in a new book, "have made a marriage in hell with their Islamic terrorist counterparts."

The defining characteristics of the 'new anti–Semitism' are taken to be firstly, that it comes from the European left, in sympathy with Palestinian extremists, and secondly, that it is expressed through criticism of Israel. Jonathan Sacks wrote in 2002 that "at times [anti–Semitism] has been directed against Jews as individuals. Today it is directed against Jews as a sovereign people." The editors of A New Anti–Semitism? give anti–Semitism a new name, Judeophobia, and say that 'vilification of Israel' is its 'core characteristic'. Israel's advocates complain that the country is demonised, singled out for unfair and disproportionate criticism, and that this reveals the presence of anti–Semitism. Anti–Semitism towards Jewish individuals becomes anti–Semitism towards a personified, victimised state, as commentators such as Harvard law professor Alan Dershowitz argue that Israel has become 'the Jew among Nations'.

It is an easy step from here to Ottolenghi's claim that 'anti–Zionism is anti–Semitism'.

But this equation is far from straightforward. Israel's defenders define Zionism as the Jews' right to national self–determination, and they argue that to deny Jews this right is to deny them something that other nations have been willingly granted. "Were you outraged when Golda Meir claimed there were no Palestinians?" Ottolenghi wondered in the Guardian. "You should be equally outraged at the insinuation that Jews are not a nation."

In response to Ottolenghi's piece, the philosopher Brian Klug noted that Zionism was from its earliest origins a controversial movement even among Jews: "When the British foreign secretary, Arthur Balfour … wanted the government to commit itself to a Jewish homeland in Palestine, his declaration was delayed – not by anti–Semites but by leading figures in the British Jewish community. They included a Jewish member of the cabinet who called Balfour's pro–Zionism 'anti–Semitic in result'." Even now, many Diaspora Jews do not necessarily identify with Israel, and question the assumption that they have an a priori affiliation with a state which is not their home country, and which is implementing ugly policies.

Reading Ottolenghi and others, it is sometimes possible to forget that calls for the destruction of Israel are essentially fantasmatic. Israel's defenders, whether anxiously or tactically, evoke the old spectre of the Jews being 'driven into the sea', often with the effect of preserving Ariel Sharon's reactionary status quo. But as a number of commentators both inside and outside Israel have argued, there are credible political solutions that lie in between Sharon and the deep blue sea.

So–called post–Zionists propose that Israel should continue as a state but cease to privilege Jews over Arabs in its laws and institutions. Others, notably Tony Judt, have mooted a one–state solution, a bi–national homeland for Jews and Palestinians alike. As Michael Rosen has written, if one regards the granting of equal rights to non–Jewish citizens as 'national suicide', then such proposals will by definition appear anti–Semitic — but only according to that particular logic. According to those who regard such proposals as fair and viable responses to the situation in the Middle East, Abraham Foxman is wrong to conclude that "the harsh but undeniable truth is this: what some like to call anti–Zionism is, in reality, anti–Semitism — always, everywhere, and for all time."

While it is hard to agree with these words, they illustrate the strength of the anxiety and exasperation circulating in this debate. The fact is that people feel the current, intense criticism of Israel as anti–Semitism, and at times, they are quite right to judge it as such. "What has been challenged is our comfort of having a foot in both worlds," Jo Wagerman, former president of the Board of Deputies of British Jews, told the Israeli paper Ha'aretz. People's experiences of prejudice should not be taken lightly."

And yet, there is also an agenda at work here. While Israel's advocates are careful to point out that they are not proscribing reasoned criticism of specific Israeli policies, their arguments tend, in practice, to serve as a warning to those who make them.

According to Alan Dershowitz, "most of the current attacks on Israel and Zionism are not, at bottom, about the policies and conduct of a particular nation–state. They are about Jews." If his critics are correct, then at least some of the current accusations of anti–Semitism are not, at bottom, about Jews. They are about politics.

Eliane Glaser works for the BBC and is a contributor to the Times Literary Supplement

To read Howard Jacobson's response to this article, click here.

To read Brian Winston's response, click here.