Daniel Johnson: Your new book, Future Tense, seems to me to be your tour de force. You've written some very important books before, but this one brings it all together. 

Jonathan Sacks: It brings it all together in terms of practical politics, really, because I haven't written all the big theology yet. This is a kind of reader in leadership of the Jewish people for the next little while and I'm glad you enjoyed it!

DJ: The central argument of the book is the split between particularism and universalism. You say Judaism is not mere optimism, but it is a religion of hope. But, nevertheless, it's quite a severe critique of the predicament in which the Jewish people find themselves today. Why, at this particular time, does the Jewish people, in a sense, doubt its own identity?

JS: Around September 1999, we got a request from the Professor of Medieval History at Boston University, Richard Landes. He is an expert in Millenarian movements, of which there were a lot in the Middle Ages: the Ranters, the Hessites, the Levellers. He had discovered in the course of his research that every millennium was preceded by a wave of philo-Semitism and succeeded by a wave of anti-Semitism. He could see, from what he'd read about the Anglo-Jewish community, that we were basking in the sunlight of philo-Semitism, and he was very anxious to tell me that all that was about to change. How it would change, he didn't know. But that it would change, of that he was certain. His best theory, and it was purely speculative, was that in September 1999, people were still worried by Y2K, the Millennium Bug, the bug that wasn't. According to the theory, come 1 January 2000, all the world's computers would crash, there would be chaos and, somehow or other, people would blame the Jews.

January 2000 came and went. The world continued revolving on its customary axis, there was no Millennium Bug and I said to Elaine, my wife: "Landes got it wrong." 

Then came 29 September 2000, the collapse of the Middle East peace process, followed by then United Nations conference on racism in Durban, which was the launch pad for a new kind of Israel-based anti-Semitism. Then, came 9/11. Within days, large parts of Asia and the Middle East were saying that this was done by Israel, by Mossad. And I said to Elaine: "Landes got it right."

We had thought that Israel was on a trajectory for peace, that Jews in the diaspora were so well integrated that the biggest problem we faced was assimilation and out-marriage. And all of a sudden we were faced by a whole series of very disturbing phenomena. 

I was caught up in all of those: this book is written from the front line, because I've been involved in anti-Semitism, the defence of Israel, the internal Jewish conversation and so on. I began to realise something I should have known, which is: if someone has experienced trauma at an early point in their life, then much later in their life it's very easy to regress to that trauma. In a certain metaphorical sense that's what happened to Jews in the last eight years: we began to hear more and more this key phrase that I analyse in the book, "a people that dwells alone". And Jews began to feel themselves isolated and embattled, with the return of anti-Semitism, the international delegitimisation of Israel and so on. 

What struck me is that this is so profoundly dysfunctional, and it doesn't answer to reality. In 1933, Jews really were alone, and there was no state of Israel, and that was the trauma of all traumas. Today, Jews are not in that situation. We have achieved equality and dignity in the diaspora, there is a state of Israel, we do have enemies but we also have friends and we should not ignore the latter.