Why is Gunter Grass held in such high regard in Germany? What does he represent?

Grass has always taken a very moral position, and in his novels and writings has often criticised Germans for their unwillingness to face the past or seek forgiveness from their former victims.

He has been respected because through his novels he created the image of an open-minded Germany, a society that could find ways of dealing with a tarnished past.

He was also very political, identifying himself from a very early stage with the Social Democrats. For example he helped rally German intellectuals behind Willy Brandt, who was the Chancellor in the seventies who tried to build bridges with eastern Europe. Grass always thought that this was the way forward for Germany - it had to make peace between the German people and the people of the east - between the heirs of Nazi Germany and the victims.

How much damage has his admission that he served in the SS done to his reputation? Why do these revelations seem so hypocritical?

At the moment when it became clear that he had not told the truth about his own Nazi past, he seemed to lose credibility with millions of older Germans - in particular those who had always slightly resented his lecturing and hectoring manner.

Now, some days after the first revelations of his SS background, the chattering classes are divided between those who still feel betrayed by him and those who say that his moral strength derives from his books and the power of his fiction rather than his biography.

How strong is the sense of betrayal among the German public this week?

I think the sense of betrayal is largely artificial. The people who are shouting loudest - above all the tabloid press - actually never read his books in the first place.

Are people cynical about all the pre-publicity that has been done in the lead up to his memoirs being released?

One theory is that the revelations were deliberately timed with the release of the book, to achieve maximum publicity. He gave an interview linked to the immiment publication of the book which was conducted by someone who had read the first proof of the book.

So of course, the outing of Gunter Grass and the book were always linked, which makes it difficult to say what was publicity and what has just happened because of a normal process. A lot of Germans are very sceptical about it all. He has been explicitly accused of manipulating his biography to boost sales.

What has his explanation been for keeping his involvement in the Waffen SS a secret for so long? Is it true his Stasi file would have been released in six months time and revealed all then?

That's just a way of carrying the story further. He has always opposed the publication of his Stasi file but there was no reason to think that there was anything comprising in that file or that he was being blackmailed.

Will this all die down reasonably soon or do you expect it will have a lasting impact on the German psyche?

There are so many Germans of his generation who were sucked into the SS in the dying days of the war that I don't think this is going to become one of the great schismatic scandals. The truth is that by the time he joined the SS there was almost nothing left of the German armed forces and he says - entirely credibly - that he never fired a shot.

One has to remember that he was 17. It's also true that a lot of German teenagers had no idea about the bad reputation of the SS. They'd swallowed the propaganda that it was a heroic elite unit. The truth is I think his reputation will survive the scandal, it's just we will have to read a little bit more carefully what he says about the last few months of the war in his earlier works.

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