Do you speak Race?
A telling moment on last night's Question Time did not involve Mr Griffin at all. It was an exchange between Jack Straw and a black woman in the audience.
This is what she said:
"The parties must listen because, one of the things, I am sitting here and every time Jack Straw or somebody or one of the panel says 'Afro-Caribbean', I am cringing."
(The justice minister holds up his hands in apology.)
"Afri-CAN Ca-RIB-bean!" the woman corrects him.
Discussing race in this country is to walk on egg-shells. When even an experienced signed-up multiculturalist like Mr Straw gets caught out, it becomes obvious how difficult it is even to find the language in which to conduct a grown-up debate about it.
When I have talked to ordinary voters about the subject, there is often discomfort over terminology. Some fear that using the word "black" might be construed as evidence of racism, so they opt for an even more contentious term - "coloured" - in the belief that this will soften their argument.
A few months ago, I received an e-mail from a Chinese viewer who told me he had been offended by my use of the word "Asian" when what I really meant was people who hailed from the Indian sub-continent. On another occasion I was taken to task for the phrase "non-white" - a shorthand for all ethnic minorities which was deemed insulting.
People generally don't want to offend and the shifting sands of acceptable racial vocabulary mean that many dare not even step into the territory. It is a dangerous domain - one false move and you are branded a bigot.
Part of the problem has been the absence of formal public debate about race. Mainstream politicians have tended to opt out or dodge the subject, so the boundaries of acceptable discourse are poorly understood - even by our Parliamentarians.
Last night's programme saw all the panellists try to shift the discussion away from the question of race onto less troublesome terrain.
"This is not a race debate, this is a debate about resources," said the Conservative Sayeeda Warsi, adding that she didn't want a BNP-style discourse "about black and brown people". (I suspect few white politicians would ever dare employ the phrase "brown people", incidentally). All are happy to see the discussion shifted onto safer ground.
Nick Griffin used the expression "indigenous British people" to describe the constituency he seeks to represent.
"The whites!" retorted Jack Straw, keen to push the BNP leader into the race debate. "Skin colour's irrelevant, Jack, skin colour's irrelevant," Mr Griffin responded, as anxious as the rest to avoid the elephant traps of a debate about ethnicity.
This is a problem because it is the recent arrival of people from different ethnic backgrounds into predominantly white communities which is the cause of one of the anxieties underlying the programme. It is not the fact that the new arrivals look different; it is that they behave differently. But neighbourhoods are being transformed because people from other cultures are moving in there. Rapid social change is often linked to ethnic change - and people are disturbed by that.
Can we talk about the alteration of Britain's racial make-up without being accused of prejudice or intolerance? It is tricky to find the words in which to conduct the conversation.
Liberal Democrat Chris Huhne told the Question Time audience that in Britain today "one in two of all Afro-Caribbean children under the age of 16 either have a white mother or a white father". Did he mean children of "mixed race" or "mixed heritage" or "dual heritage" - or whatever the acceptable expression is these days?
Here again we have an important and complex issue - the rapid growth in the numbers of children who don't fit into conventional racial or ethnic categories. There is evidence (see, for example, this Home Office paper [55Kb PDF]) that such youngsters perform less well at school, are more likely to abuse drink or drugs, to end up in prison, to face prejudice or discrimination. But, as I discussed here last year, we don't yet have the language to engage with the intricacies of this.
Globalisation has seen the development of what has been called "identity politics". The trouble is that the debate can barely get beyond issues of classification.
"It is genuinely racist, it is extraordinarily racist when you seek to deny the English... you people wouldn't even let us have our name on the census form," Nick Griffin said last night. "That is racism and that is why people are voting British National Party."
Unable to define who or what we are talking about, we are unable to define the debate. "We are the aborigines here," Nick Griffin said last night. "All of us are descended from Africa," responded the playwright Bonnie Greer.
The British people, I think, are broadly tolerant and welcoming. We don't wish to offend or make a scene. That said, there is deep concern about how racial and cultural convergence is altering our way of life, and yet we struggle to find the words to voice those fears.