Ephraim Halevy, former head of Mossad, tells a great story about his time as Israel's ambassador to the European Union in the late 1990s.

While wandering the Brussels corridors he discovered there was an official with responsibility for "special cultural affairs" who ran a mysterious outfit called the Cellule des Etudes ("The Study Cell").

When he made further inquiries he came to the conclusion that the official was crafting a common policy on how to deal with the rise of radical Islam in Europe. When he raised the issue with the official's superiors he understood that this was something they preferred to keep very much behind closed doors.

Mr Halevy told this story at the Herzliya conference as a response to David Cameron's speech on multiculturalism, to illustrate how times had changed. The prime minister's speech, made last weekend at a security conference in Munich, was the talk of Herzliya, to which many of the delegates had travelled straight from Germany. Although Mr Cameron's speech initially elicited a hostile reaction in some sections of the left in the UK, there is now a growing consensus that he was absolutely right to speak out.

The key passage was a challenge to organisations, including the Muslim Council of Britain itself, which claim to represent Britain's Muslims: "Let's properly judge these organisations: Do they believe in universal human rights - for women and people of other faiths? Do they believe in equality of all before the law? Do they believe in democracy and the right of people to elect their own government? Do they encourage integration or separatism?"

It is possible to take issue with the timing of the speech, coming as it did as the English Defence League was marching in Luton.

But it was not an attack on Muslims, it was an attack on separatism. It is quite possible to have a well-defined identity, while being integrated with British society, as the Jewish community has long demonstrated.