‘SEND. Her. Back!” So that’s how it’s going to be now. Not “lock her up” but “send her back”. Three days after telling four left-leaning Democrat congresswomen to “go back” to the countries they “originally” came from, and the same day as the House of Representatives condemned him as racist, an energised Donald Trump was sending a crowd of supporters into paroxysms of ecstasy at a rally in North Carolina. This time, Mr Trump was serving up racism with his misogyny, and they revelled in it. The mere mention of Somali refugee Ilhan Omar (Rep. Minnesota), a Muslim woman who wears a headscarf and is the only one of the four to be born outside of the US, had them baying for her deportation.

This is the real story of the last week. Donald Trump’s racism is about as subtle as his quiff and always has been. But increasingly we are seeing Republicans delight in his racist tirades: his approval ratings among party members rose by five per cent in the wake of the tweets. A president who’ll boot political correctness to kingdom come? They couldn’t get enough of him.

In three years, Mr Trump has transformed the Republicans from the big tent party of Reagan and Bush, into a suspicious, mistrustful, angry sect. He has torn off the veneer and revealed the seething resentment underneath. He has revelled in it and is now seeking to use it to propel himself all the way back to the White House.

And he has done this almost entirely with words. Simplistic, inaccurate, often downright absurd words. Petulant words. Self-pitying words. Words that, in their very inarticulacy, resonate deeply with voters alienated by the high-flown oratory of Barack Obama. Words that respect no boundaries. If Mr Trump is an iconoclast, then political correctness is lying smashed at his feet.

Will it be mourned? Well, it certainly should, because without it, we are sliding back to the 1970s. In the UK too, where the Prime Minister-in-waiting Boris Johnson has bated Muslims just to endear himself to an increasingly radicalised Tory Party membership, considered speech can no longer be taken for granted, even at the highest levels of politics; in its place is polemic and sneering derision.

It is tempting to argue that the PC police had gone too far, that nursing hurt feelings had become a full-time occupation for some and that public officials were taking matters too far. Perhaps. Banning all religious references in children’s “Christmas plays” is one example. But snagging on these passing headlines is to miss the bigger picture and the real significance of this phenomenon: language is one of the only weapons against hate that we have. If we abandon kind and respectful language, then vicious words and deeds will surely follow. It’s already happening.

In the 21st century, political correctness has been co-opted as a term of abuse to dismiss anyone, particularly those advocating for women, the disabled, ethnic minorities, transgender people or other traditionally marginalised groups, who suggest that we should exercise some thought about the words that spew from our lips. As such, it is a source of the most volcanic irritation for many people. You’ve heard the sort of thing. They don’t see why they shouldn’t be allowed to say what they want; Britain is a free country isn’t it? Frankly they wouldn’t be at all surprised if there was an EU regulation outlawing the habit of calling waitresses “love”. And in fairness, like many of us, they are afraid of inadvertently falling foul of the rules and being branded a bigot for getting the terminology wrong. (Even Benedict Cumberbatch, for all his expensive education, has done that.)

But at its heart, political correctness upsets people because examining the words we use and the assumptions we make about others forces us to confront our knee jerk beliefs about them. And those might not be quite as kindly as we’d like to think.

That is why it matters. Anyone can incubate prejudice without meaning to; after all many of us, to some extent, live in a bubble, whether racial or social or economic. It does no harm to examine our beliefs from time to time.

We just need to relax about it. After all, most of us exercise political correctness in our personal lives every single day.

Because what is being PC except editing the thoughts that spring to your mind before they exit your mouth, so as not to cause unnecessary hurt? It’s just showing consideration by another name. We all do it all the time. Most of us, seeing a friend in the street, would resist the temptation to comment on her expanding girth. Mothers and fathers don’t usually tell their kids that their singing is a bit rubbish. We’ve all received gifts that have made our hearts sink but only a truly malevolent soul would drop the china unicorn into the bin right in front of Auntie Sue. We exercise self-control to protect other people’s sense of self-worth. And extending that courtesy to strangers helps to protect them in the same way in an increasingly hostile world.

Some see all this as a veneer, arguing that kind words don’t necessarily denote kind thoughts.

Undeniably. But kindness and consideration in our language, when all public figures adhere to the same rules, provide a sort of herd immunity by making it socially unacceptable to voice your darkest impulses in public. When this consensus is abandoned by the likes of Donald Trump and Boris Johnson, the prejudice lurking beneath is validated and the bigotry normalised.

Mr Trump and Mr Johnson, who both spin themselves as honest and open, are in truth cynical and manipulative. Mr Trump knows that endorsing racial prejudice will galvanise his supporters and might win over some Democrats in marginal states, and Mr Johnson has been playing a Tory membership that believes overwhelmingly that parts of the UK are under Sharia law.

The invasion of the public space with racist, misogynist, anti-immigrant and anti-LGBTI views – views that some of us had dared believe were in terminal decline in supposedly advanced democracies like Britain and the US – is a reminder that progress is not linear.

The property mogul from New York has gloried in abandoning the consensus around measured, respectful language. He can’t be allowed drag us all with him. It’s time, you might say, to send him back.

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