Who is going to educate young people about the Holocaust when the survivors are no longer with us?
That is the question I keep asking myself in the days leading up to Holocaust Memorial Day on 27 January 2014. Because the further we get from the end of the Second World War, the fewer survivors we have to share their powerful stories.
During a recent book tour in the USA I was hosted by a Holocaust educator in each city, and every one of them told me that they were worried that they would soon have no survivors to help them with their work.
And they have good reason to worry.
To have a Holocaust survivor talk to a group of young people is a precious thing. It makes the tragedy real, visceral. It has impact.
I have seen this frequently. The room goes quiet. The survivor tells his or her story. The kids are changed.
I observed this at one of my book events. I had been speaking for over an hour, people were growing restless, one man even asked if it was time for lunch. Then a survivor stood up, the room hushed. With a microphone to her trembling lips she said that when she had left Auschwitz she had weighed fifty-eight pounds. In those few words she said so much more than I ever could in an hour. It was terrible. She had survived. And she was brave enough to tell the tale.
When I spoke to an expert at the US Holocaust Memorial Museum, in Washington DC, she said that they are well aware of the issue, they even have a name for it, the 'post survivor era.'
A lady who works at one of the leading Holocaust research centres in England told me that they are carrying out a 'strategic review' on the subject.
But most people I ask tell me not to worry so much. 'We have thousands of hours of interviews with survivors,' they say, 'We have books and graphic novels. We have artefacts, memorials and exhibits.'
All of which I know, and is good, but it is not quite the same. And I do worry, especially about the teaching materials.
When I ask which books teachers are using I am told, "Well, there is the Diary of Anne Frank". It has sold millions of copies, it has been translated into scores of languages, it's true and it's powerful. Fair enough.
What else? I ask. "Well," they say, now wincing, each and every one of them - from Brooklyn to Birmingham, from North West Washington DC to North West London - "teachers are increasingly using the Boy with the Striped Pyjamas." They add, it's an easy teach: it's about children, it's very well written, there's even a movie the kids can watch.
For those who don't know, the Boy with the Striped Pyjamas is about the son of a concentration camp kommandant who befriends a Jewish boy prisoner. While fictional, it is clear that the story is largely based on the family of Rudolf Höss, the Kommandant of Auschwitz.
Now I know a little about Rudolf Höss' family. In 2009, I travelled to Auschwitz with Rudolf Höss' daughter-in-law and grandson, and then a couple of years later, I interviewed Brigitte, the Kommandant's eighty-year-old daughter, who now lives outside of Washington DC.
And I can tell you, having spent time with the Höss family, with a great degree of confidence, that the Kommandant's children never played with Jewish kids, let alone befriended them. To the contrary, the Höss children pinned triangles and stars to their shirts and pretended to be prisoners, like Cowboys and Indians.
So we have a second problem, a fictional holocaust is increasingly being taught to kids.
This week I gave the annual Merlyn-Rees Lecture for the Holocaust Education Trust at the Houses of Parliament in London. The room was packed, with over three hundred people: camps survivors, Members of Parliament, journalists and students. The audience was alert, committed, and eager to learn.
Afterwards at dinner, I sat next to Holocaust survivor, Ben Heflgott. He told me that when he was nine-years-old he had been forced into a ghetto in Poland, a few years later he was sent to Buchenwald and then Theresienstadt. With the exception of one sister, his entire family was murdered by the Nazis. Now, almost seventy years later, I asked him what he thinks about holocaust education in the so-called 'post-survivor era'.
He put down his fork, turned to me and said, "it's simple, the next generation will have to do it. And they will be even better."
That is the answer to my question. We will just have to do it. Better. It is that simple.
On 25 February, Thomas Harding will be talking about his book 'Hanns and Rudolf: The German Jew and the Hunt for the Kommandant of Auschwitz' as part of Jewish Book Week