The degree to which an insult can wound depends hugely on how it is said. A racist taunt, spat out on the street by skinheads, is an appalling abuse: cruel, demeaning and incendiary. The same taboo words, if used in a wholly different context, do not necessarily prove malign intent. To brand Prince Harry a racist because of a remark recorded on video three years ago is absurd. But to suggest that what he said was not offensive and, to many people, insulting is also wrong. He was right to apologise. But it will be some time before the unpleasantness caused by his foolishness dissipates.

Over the years, attitudes to racial abuse have, rightly, hardened. What was considered a generation ago as merely jocular, old-fashioned or mildly unkind is now seen as deeply offensive. Partly this is because Britain has become more truly multicultural and sensitive to the dangers of prejudice. Partly it is because race, despite vast improvements in integration, understanding and social cohesion, remains a dividing factor that is easily exploited by bigots and demagogues.

That is why successive governments have drawn up legislation to outlaw the incitement to racial hatred, set up commissions to monitor race relations and given police the power to arrest those who abuse the freedom of speech to exacerbate ethnic and religious tensions. To a large degree, this has been effective. But laws are less important than public attitudes. At a time when most former taboos, particularly on swearing and obscenity, have lost much of their force, those on racial insults have grown stronger. Schools, the media and public figures have all done much to change attitudes. This is not a question of enforcing political correctness; as those originally arguing for more sensitive language realised, public acceptance of mildly distasteful jokes on race or gender can easily legitimise harsher and nastier attitudes.

The old proverb about sticks and stones breaking bones may be true for people with confidence in their rights and place in society. But for minorities, who may have encountered prejudice and discrimination, words can indeed be a weapon to undermine dignity, self-confidence and eventually normal human rights. Some people are able to brush off foolish remarks. Robust dismissal is always the more effective response. Others, however, fear that slights about their race, gender or religion betray a subtle antipathy against which they have no effective defence.

The more public a figure, the greater the responsibility not to give offence. After the absurd fancy dress fiasco a few years ago, Prince Harry should need no reminder that a prominent member of the Royal Family is a public figure, even in private. His supporters will argue that he is in an impossible position: urged by the media to be “normal”, he must nevertheless police every word and action, as the media will miss no opportunity to create a scandal out of some ill-judged utterance. This must be doubly difficult in the Army. The culture of those on the front line is not known for linguistic sensitivity.

But there is a world of difference between an obscenity uttered in anger and a remark intended as a joke that is not only racist but patronising. Too many Asians have been insulted by the epithet “Paki” to shrug it off. It is offensive. It should be used neither in anger nor in jest.