Robin Shepherd is not the first person to try and define the world's oldest hatred, but he is perhaps one of the most unlikely. The senior research fellow at the Chatham House think tank in London has no significant connection to the Jewish people, and his visit to Israel last week was only his second. But he still believes his decision to spend a year researching the new European anti-Semitism is perfectly relevant for any serious observer of international affairs.

When asked about his interest in the subject, he first answers on a philosophical level by quoting the polemicist Christopher Hitchens, who has said that "only a moral cretin thinks that anti-Semitism is a threat only to Jews." He then offers an academic explanation: "The Israel-Palestine conflict is one of the key issues in international relations, and there are very few people in this field without a position on it." His last work was on the wave of anti-Americanism sweeping Europe, and this led him to believe that a new form of anti-Semitism was also at the root of the increasingly critical attitude toward Israel there.

Shepherd is only beginning what he expects to be a year of research on the subject, probably culminating in a book, but he already has a number of basic insights. The first is a clear differentiation between the old and new European anti-Semites, or as he puts it, "subjective" and "objective" anti-Semitism.

"Subjective anti-Semites basically hate Jews and therefore usually hate the Jewish state," he says. "There are people in Europe who are hostile to Jews, but it's only on the fringes, in the far right and far left."

Interestingly, Shepherd notes that the old-style anti-Semitism is still fairly prevalent in post-communist Central and Eastern Europe, but at the same time, there's much less anti-Zionism there as compared to Western Europe.

"A much bigger problem is the objective anti-Semitism, the hatred of the State of Israel," he says. "Since Israel is a Jewish state, and if you use false analogies between Israel and Apartheid South Africa and Nazi Germany, you are comparing them with Jews and you are therefore engaged in anti-Semitism."

That doesn't mean that everyone who uses the comparison is an actual anti-Semite, says Shepherd. "That depends on how central [this comparison] is for you. When it becomes an obsession - and this is one of the things you find increasingly in Europe - then at this point it becomes a new form of anti-Semitism."

This is Shepherd's answer to the standard response by Israel's detractors in the West, that "not every criticism of Israel is anti-Semitism."

"Of course one can criticize Israel, but there is a litmus test, and that is when the critics begin using constant key references to South Africa and the Nazis, using terms such as 'bantustans.' None of these people, of course, will admit to being racist, but this kind of anti-Semitisim is a much more sophisticated form of racism, and the kind of hate-filled rhetoric and imagery are on the same moral level as racism, so gross and distorted that they are defaming an entire people, since Israel is an essentially Jewish project."

To explain this distinction, he cites Zimbabwe as an example. "A lot of people will defend themselves by saying that their motivation is the cause of the Palestinians. Well, if you wanted to express your disapproval of Robert Mugabe's regime by highlighting his violation of human rights and the way he's destroying the country, then you could say your motivation is human rights, but if you expressed your objection with a cartoon of Mugabe as a gorilla jumping up and down on blood-soaked bananas, that kind of imagery of black people is pure racist. But it's the kind of imagery being used against Israel."

The enemy's enemy

Shepherd studied Russian and East European studies at the University of London and completed an advanced degree in political philosophy at the London School of Economics. After that he worked as a reporter for Reuters in London, Prague and Bratislava and was the Moscow Bureau Chief for The Times of London for a year and a half. In 2003 he left full-time journalism for a number of research centers and think tanks, in order "to focus more on the analytical side," though he still writes occasional commentary and opinion pieces for various newspapers. He considers himself "center-right on international affairs, with very liberal social views." He attributes the rise of the new anti-Semitism to the crisis of the "old ideological left" in western Europe.

"The main thrust is coming from the left wing of the old European labor and social-democratic parties, and of course from the surviving Communist, Trotskyite and Marxist parties. These are groups that might have a marginal place in wider society, but their influence is focused in the trade unions, which are boycotting Israel, and the opinion-forming classes, such as the media.

"The ideological left has been comprehensively defeated, and it knows it. That's why it has no positive campaign as it had in the past, like nationalization of the economy. In the absence of a positive program, it is about what they hate - the U.S., the global capitalist economy and the State of Israel, because Israel is the frontline to the only force that is challenging all that, the Arab world. That is why, despite the horribly reactionary attitude of the Islamic radicals toward women and gays, there is a common cause - my enemy's enemy is my friend," he says.

This feeling is largely absent in the former Communist countries. "These groups are weak in Eastern Europe because they've been thoroughly discredited. In Poland, for example, politicians do occasionally come out with anti-Semitic sayings, but it doesn't translate into anti-Zionism. These feelings are concentrated more in countries like Britain, Spain, parts of Belgium, Norway and Sweden. France and Germany are interesting countries, because the political classes are generally different in this from the opinion-forming classes, but it might be feeding through."

Religion of politics

Israel's poisonous critics who say they are not anti-Semites often state that there are prominent Jews among their ranks. Shepherd says this is one of the most interesting points that he plans to research.

"I know there is a tendency to call them self-hating Jews, but the key point is much more subtle. This is where you have to understand people like Noam Chomsky, who is American but an iconic figure for the European left. He is not a self-hating Jew, but his political standing in the left is more important for him than his Jewish identity. That's why the extreme Jewish critics of Israel almost always come from the far left - for them, politics is the most important part of their identity. They are in thrall with a system of thought that happens to have as one of its main objects of belief an obsessive hatred of Israel.

"It might be personally painful for them, but the ideological left is a secular religion, more than any other political group, and for them this religion comes before being Jewish," he says.