On Friday morning David Cameron called upon David Miliband to apologise. On Friday evening I went to see a play. The play was Our Class, by the Polish playwright, Tadeusz Slobodzianek.

In a series of short “chapters” Slobodzianek followed a group of classmates in a small Polish village from 1925 to 2002. Like the village, the class was half Catholic and half Jewish. In 1941, as the Germans replaced the Russians as the occupiers, almost all the Jews of the area were murdered in a single day. Slobodzianek shows what led up to the massacre and what happened afterwards. It is unbearable.

Though the village is not named in the play, it is based on real events that took place at Jedwabne on July 10, 1941. As Poland’s Institute of National Memory concluded in 2002, on that day 40-50 Jewish men were forced to parade around the town singing songs, and were then led to a barn on the outskirts where, one by one, they were killed with knives, axes and cleavers and then thrown in a pit. Then 300 or more women and children were led from the town square to the barn and locked inside. Kerosene was poured over the roof and walls and set alight. The screams could be heard from two kilometres away; no one survived.

In 2001 it was finally acknowledged what many people had known all along. The murderers hadn’t been Germans, but local Poles, as depicted in Our Class. Alexander Kwasniewski, then the Polish President, apologised to the dead Jews and their survivors at a ceremony in Jedwabne “in my own name, and in the name of those Poles whose conscience is shattered by that crime”.

History matters. Few believe that as much as the Law and Justice party of Michal Kaminski, who leads the Tory-backed group in the European Parliament. The party’s leaders have demanded apologies from the Russians for the massacre of 21,000 Polish officers at Katyn in 1940 and their references to terrible Polish historical suffering have constituted a big part of their political appeal.

But despite his historical sensitivity Mr Kaminski, the MEP for the Jedwabne area, did not support the 2001 apology. He opposed it vigorously, associating himself with the “Committee to Defend the Good Name of Jedwabne”. Among its leading members were the local priest, Edward Orlowski, who — asked by journalists whether he would be attending the ceremony at which the President apologised — said: “These are all lies. It is not my business. Germans are responsible, so why should we apologise?”

Mr Kaminski developed a slightly different rationale. As he told an interviewer for a far-right newspaper, Our Poland, the murders — which he abhorred — were the work of a few outcasts, and that he would only apologise if someone “from the Jewish side” apologised for how “the Jews” behaved during the Soviet occupation from 1939 to 1941. Last month Mr Kaminski (who had denied giving the interview) confirmed this position. “If you are asking the Polish nation to apologise for the crime made in Jedwabne,” he said, “you would require the whole Jewish nation to apologise for what some Jewish communists did in Eastern Poland.”

It is this argument that so incenses me, as it would anyone, I think, who had sat through Our Class. The idea of collective Jewish Bolshevism was a major anti-Semitic trope before the war; it was a major element of self-justification after it.

Mr Kaminski denied the apology, denied the need for it, equated the massacre to “Jewish actions” and allied himself with those who denied the massacre altogether, fulfilling the historian Pierre Vidal-Naquet’s observation about patterns of massacre denial: “It never happened, it happened but was justified, they did it to themselves, they did it to us.” Mr Kaminski’s view was described as disgraceful by Mr Miliband. Having read an enormous amount on Jedwabne in the last few weeks, I think Mr Miliband is completely right — it is disgraceful. And as he might well demand of Mr Cameron: “I should apologise?”

But more than that, I find myself amazed by how Mr Cameron ever came to be in the position of demanding that a foreign secretary, descended from Polish Jews, should apologise for possibly offending the sensibilities of a foreign politician who vehemently opposed there being an apology for the massacre of Polish Jews. I think of all the things that Mr Cameron has got right in his leadership of the Conservatve Party and my mental jaw drops at the sheer wrongness of it.

Now Tory columnists, bloggers and activists are devoting their time to nitpicking sophistry about the nature of collective guilt, and to attacking non-existent “smears” that they say have been attached to the unlovely person of Mr Kaminski. Why?

It is true, as embattled Conservatives have argued, that many of the grand European coalitions contain people whose history is problematic. There are odds and sods in the big conservative grouping, the EPP, and in the socialist group. But these personalities are far outweighed by the parties of the Merkels and Sarkozys. The Polish member of the EPP, for example, is the ruling free-market, non-nationalist conservative party of Donald Tusk — almost certainly the party that Mr Cameron would join if he were a Pole. The new Tory grouping, the European Conservatives and Reformists, by contrast, is all about odds and sods whom a continental Cameron would certainly shun, bar one organisation — the British Conservatives.

So why get yourself into a position where you have to explain that the Latvian SS wasn’t so bad really, and that Mr Kaminski has an understandable position on collective guilt? And the answer seems to be that Mr Cameron promised his Europhobes in his leadership campaign back in 2005 that he would leave the “federalist” EPP, and that the logical outcome of this move has been the weird alliance that he now finds himself defending.

Was it all necessary? No. Was it in Britain’s interests? Absolutely not. Is it in the interests of progressive Conservatism? You must be joking. So has this happened because Mr Cameron doesn’t really care enough about Europe to think through the consequences of his own lightly given promises, or because he’s just as much a Euro-nutter as those sects, the Hannanites, the Cashists and the Redwoodians?

This is the kind of advice I loathe, but I’ll say it anyway. Go to see Our Class, Mr C. This is one hole you don’t want to keep digging.

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