Criticism of Israel is certainly legitimate, as is criticism of any country. I am myself critical of its policies. But a line has been crossed into something else - the demonisation and dehumanisation of Israel based on systematic lies, libels and distortions. As a result, a lot of decent people have been unwittingly caught up in a narrative of hatred.

Former Sunday Times editor Sir Harold Evans tried to show where that line should be drawn. It was not anti-Semitic, he said, to report Israeli ill-treatment of Palestinians or Sharon's past, or to deplore the long occupation of the territories. It was anti-Semitic to present Israel as diabolical, to invent malignant outrages, to condemn actions by Israel while not condemning worse elsewhere, and to vilify Jews so as to incite violence.

In all four categories, that line has been crossed. Diabolical? Israel is routinely described falsely as an apartheid or, worse, Nazi state. While its society is far from perfect, Arab Israelis not only have the vote but serve in the Knesset, supreme court and army. To label it 'Nazi' is to delegitimise it.

Malevolent outrages? Look at the so-called 'massacre' of Jenin, which has become an accepted fact even though there was no massacre: 23 Israeli soldiers and 52 mostly armed Palestinians died in that incident. There are some appalling and inexcusable incidents in Israel. But that doesn't explain why Israeli self-defence is systematically and falsely represented as malevolent aggression.

Double standards? British academics try to impose boycotts on Israeli universities. Yet they organised no boycotts against Kuwait, which expelled 350,000 Palestinians in 1991; or Jordan, which murdered tens of thousands of Palestinians; or Syria, which has occupied Lebanon. And increasingly, people are saying Israel should not exist at all, thus singling it out alone for destruction.

Inciting violence? People such as Lib Dem MP Jenny Tonge have come close to excusing the mass murder of Israelis in a manner they would never apply to the mass murder of other peoples.

Coverage of Israel is obsessive and disproportionate, and marked by a hysteria and malice not applied to any other conflict. And it cannot be divorced from the overt Jew-hatred that has now surfaced in Britain and Europe, particularly the give-away calumny of world Jewish power. The claim that Jews conspire to dominate the world is one of the oldest tropes of classic Jew-hatred. Astonishingly, claims made by the European Left are not far removed. It repeats claims that the 'powerful Jewish lobby' is now running American foreign policy. When Labour MP Tam Dalyell observed that a 'cabal' of Jewish power was behind Blair, he was thought a loveable eccentric. In the House of Lords, a meeting heard that Jews control the British media. One peer told a Jewish colleague: 'We've finished off Saddam. Your lot are next.'

The outcome is that an astonishing axis has developed between Islamic Jew-haters and the Left, marching behind the banners of 'human rights' on demonstrations in Europe producing chants of 'Hamas, Hamas, all Jews to the gas'.

Why? The main reason is ignorance of both the Middle East's history and its present. Next, the Left's hatred of Sharon is so great, along with its prejudice that America/the West is the oppressor and therefore the Islamic/Third World the victim, that it can't see what is happening.

Then there's the Left's deconstruction of the very concepts of objectivity and truth, so that it has become a conduit instead for propaganda and lies; and finally, its own history of Jew-hatred from Marx onwards. The final twist is that there are some Jews on the Left who subscribe to all the above too.

Former Archbishop Desmond Tutu said people were scared to say the Jewish lobby in America was powerful. So what? he asked. 'The apartheid government was very powerful but today it no longer exists. Hitler, Mussolini, Stalin, Pinochet, Milosevic and Idi Amin were all powerful, but in the end they bit the dust.'

So Jews not only have vast power, according to Tutu, but are on a par with those tyrants. Yet it was Tutu who could publish this calumny about the Jewish people, and thus incite yet more to hate them. But of course, any Jews who call this by its proper name are the new McCarthyites.