Obama knew that Mourdock was essentially outlining the position of any observant Roman Catholic – that an unborn child’s life was precious no matter how it was created. But Obama told the Leno audience: ‘Rape is rape. It is a crime. And so these various distinctions about rape don’t make too much sense to me.’

Mourdock – never mind Romney – made no distinction about different types of rapes or characterised rape as anything other than a crime.

What Obama was doing was what he was doing in his Las Vegas speech – playing on the fears of voters that Romney is a crazed bigot.

As the laundry list of minority voting groups indicated, Obama was engaging in what one politician described in 2008 as ‘the kind of slice and dice politics that’s about race and about gender and about this and that, and that’s what Americans are tired of because they recognise that when we divide ourselves in that way we can’t solve problems’.

That politician, of course, was Obama, then running for president.