I went to the Labour Friends of Israel fringe in Liverpool last week to hear what Ed Miliband had to say about his decision to back the Palestinian bid for observer status at the UN. As a result, I heard one of the funniest, most moving and eloquent speeches of the conference season. Unfortunately, it was not made by the Labour leader, but by the new Israeli ambassador Daniel Taub.

Mr Miliband trotted out a few tired jokes, had an ill-advised pop at Michael Gove, one of the most popular politicians with the Jewish community, and told the audience he understood that his new direction on Israel-Palestine might be difficult for some people present.

What followed was a masterclass in speechmaking from Mr Taub, who combined moral authority with an impeccable sense of comic timing. This is a difficult trick to pull off and I will not presume to replicate it here.

However, there was a story Mr Taub told which acted as a direct challenge to left-liberal supporters of the Palestinian cause. He said he had recently attended an event where anti-Israel protesters had been present. He used the occasion to show them a short film of a Palestinian terrorist cornered in the street and in fear of his life.

In order to protect himself, the man grabbed a passing child and held him up, quite literally, as a human shield. The challenge for progressives, he said, was to decide which of the two Palestinians to support, the terrorist or the boy.

I am told Mr Miliband was unhappy that Mr Taub had been so direct in his criticism of Labour policy. He must also have realised he had been thoroughly upstaged.

The distinction made by Mr Taub may be a little hyperbolic: there is no suggestion that the Labour Party supports Palestinian terrorists, and Ed Miliband, like every decent human being, would side with the little boy every time.

But great speech-making is about holding people's attention. Mr Taub gave the Labour leader a basic lesson in speech-making; sometimes you have to grab people by the balls to make them feel your passion.