He is a man of contradictions, Ari Shavit. A veteran of the peace camp in Israel who sees huge deficiencies in the Oslo Accords and who wholeheartedly endorses Prime Minister Benjamin Netanyahu and peace negotiator Tzipi Livni in their insistence that the Palestinians recognise Israel as a Jewish state. A clear-eyed, dispassionate analyst of Israel’s woes who is yet a passionate Zionist and, possibly to his own surprise, a passionate Jew.

Mr Shavit’s book, My Promised Land, has won plaudits around the world for its many-layered diagnosis of the Israeli condition. This week he was in the UK and such was the demand to hear the Ha’aretz columnist that one more session was slotted into Jewish Book Week’s timetable in addition to his appearance with Jonathan Freedland of the Guardian.

He had, he said, wanted to write this book for more than 20 years. (It has only been published in English but a Hebrew version is in the works.) “This book came to answer a real existential need of mine. I write from within, out. This is a very Jewish book. It is the book of a passionate Jewish, Israeli Zionist, who is trying to decipher his own nation.”

Mr Shavit insists that there is no bitterness in his book. “I think that what I tried to do was to love Israel in a new way. People have divided into those who support Israel and refuse to see its mistakes, and those who criticise it — and I’m not talking about the Israel-haters here — in an increasingly cynical way. I say, let’s look at it as it is, with all its flaws, with all its sins. And once we do that, it’s such a remarkable human story. I see Israel as a triumph of the human spirit facing the terrible tragedy of the conflict.”

Labour Zionism, says Mr Shavit, was heroic in an almost incomprehensible way in terms of what it achieved for the young state of Israel. “For us, the Yom Kippur War of 1973 was our First World War. After it, the ancien regime collapsed and what I claim is the flaw followed. The generation that succeeded it — the peace camp, of which I was a part — focused only on the peace agenda, rather than look at the nation as a whole. That is why it failed to succeed.”

I tried to love Israel in a new way, to look at it with all its flaw

Mr Shavit adds: “I saw the flaws with the peace movement when Oslo happened [even though] I totally supported the attempt. I thought that the attempt to try to end the conflict without having a recognition by the Palestinians of the legitimate rights of the Jewish people, and the right to have a Jewish state as a legitimate entity, was a deep mistake. I thought then, and I think now, that that was the conceptual flaw of Oslo.”

There was a delusion on the Zionist left “that the conflict was all about 1967 and that it would end with the end of the occupation. My claim was that there are two different issues: the issues of settlement and occupation, on which I think the left was right; but the left was totally wrong assuming it’s all up to us, and that if we would just withdraw, then there will be peace. Everything that has happened in the last 20 years, in which Israel tried time after time to make peace and was met with violence, has proved my doubts were correct.”

Mr Shavit, with a nod to his British ancestors and his Anglophilia, says he wants to keep the debate rational and courteous. He regrets that Israel has not translated its “great energy to sober rational behaviour”.

Yet Mr Shavit is still proud of and confident in Israel. He supports US Secretary of State John Kerry but cautions that Israel needs to adopt “a new peace concept”. It needs to be more humble, more British. It needs to be step-by-step and there needs to be a “Plan B” if the talks fail. He is beginning to sound like a politician in the wings, but he smiles and says that while he is willing to do a lot to help his country, becoming a politician is not on his agenda. Yet.