In the last month or so the scales have slipped from my eyes. Something I never used to understand has — almost in a lightning flash — become clear to me. It happened even before all those Palestinian flags materialised at the Labour conference.

It seems obvious to many of my generation that you see a wrong thing, you make a fuss about it. You see what you think is prejudice, you call it out. The taxi driver tells you he doesn’t much like black people, you suggest he keep it to himself. You don’t just let it go, because we know where letting it go leads.

But it does mean that you sometimes look back on your not so distant ancestors with an almost embarrassed surprise. There they were in safe Western countries, and they were too scared to say “boo” to a goose. How unnoble was that?

Take the Jews of Canada in the 30s or 40s. I came across a report this week of a conference in Montreal not so long ago looking at what had happened to Jewish refugees from Nazism who had fled across the Atlantic. A historian at Montreal University, Max Beer, had presented a paper entitled Holocaust Survivors and the Montreal Jewish Community.

And what he showed was that the Montreal Jewish community had been desperately worried that too many refugees would stoke antisemitism in the province of Quebec. They felt that their position even in a country like Canada was precarious. When they did hold events to protests against what the Nazis were doing in Germany, they would make sure the front seats were filled with non-Jews so that people would not accuse them of always looking after their own interests. In an interview, Max Beer explained that “Everything had to be presented from a non-Jewish point of view. They had to make it appear that it was a universal cause. The message was that everyone was the victim of Hitler.” Even so, when war came, there were plenty of Quebecois who would argue that it was a “Jewish war” fought with Canadian blood.

In 1944 in elections for the Quebec provincial government, the Union Nationale Party leader, Maurice Duplessis, claimed that the ruling Liberal party was taking money from the “International Zionist Brotherhood” to settle 100,000 Jewish refugees in Quebec.

Pamphlets were handed out depicting a rich, hook nose Jew handing out money to officials while in the background a great crowd of dirty, villainous looking, big-nosed Jews lurked ready to enter. Duplessis won the election.

This appeared to many in the Jewish community to be a vindication of the ”keep shtum” strategy. “You are here on sufferance and if you make a fuss, these people may turn on you. Don’t stand out. Talk nice, even if inside you feel not nice at all.” And that was a big part of Jewish community thinking in Britain as well.

All of a sudden I understood it. Because, and this is a terrible thing to have to say, I think the stand the community took — loudly and proudly — against antisemitism has actually had the effect of increasing it. I look around and I see that there are many more people on the Left who now believe that there is a conniving Jewish/Zionist lobby, out to smear their heroes in order to defend their interests (in this case, Israel) than there were before the Enough Is Enough protest took to Parliament Square. Put simply, in a choice between JC and the Jews, a significant number of people on the Left have chosen JC.

Quite a few of them, of course, don’t know many Jews and even fewer know what you might call “community” Jews. It’s been all too easy for Jewish protests against Labour antisemitism to be depicted as a vendetta by a powerful and frankly slightly exotic group against a Christlike figure. It’s going too far to suggest a deep and almost medieval Christian symbolism to all this, but you do wonder sometimes.

Loud Jews, noisy Jews, demanding Jews are not the Jews people like. People like soft Jews, quiet Jews, oppressed Jews to weep over.

I am sure that some of those ordinary Labour delegates waving flags of a place that six months ago they’d have been hard put to find on a map, are genuinely concerned first and foremost with the plight of Palestinians.

But for others those flags were as expressive as a two-fingered gesture to a group of people they could do without.