JUST at the point where I thought I had reached the zenith of horror in my reactions to the USA presidential debates, I was caught off-guard. Googling the American vox populi in the aftermath of the final presidential debate this week, I came across a video clip of an interview with a middle-aged Republican delegate from Montana.

To set the scene, she was dolled up in a kind of homespun, pound-shop Stars and Stripes cowboy outfit, her statement jewellery piece a big'n’brash plastic badge pinned to her waistcoat, declaring: “Hot Chicks for Trump.” The crowning glory to this get-up was a large and, undoubtedly, bespoke foam cowboy hat that appeared to have undergone dual-purpose customisation so that it could be worn seamlessly to either a Republican or, with a quick tilt of said headpiece, a leprechaun convention.

The gist of the journalist’s questioning in this clip was about the practicalities of building Trump Wall between Mexico and the USA. When pushed by the journalist on how this would be done, the cowboy/leprechaun delegate thought hard for a bit and said: “Well, I would pattern it after the Great Wall of China.” Prodded further about the possibility that people (presumably Mexicans) might try to climb over it and what would she do then, she replied: “Personally, I'd shoot them … they're invading our country.”

There wasn't a hint of shame or circumspection in her response. Clearly, she felt God was on her side of the wall. As for those who lived on the other side of the wall, frankly (my dear), she couldn't give a damn. The problem is that when "the others" means all that is "not me", or not "my tribe", it cancels out an awful lot of souls on our planet

We all build walls around us. If we have had a bad experience and sustained a deep emotional wound or trauma, the wall is essentially protective. Sometimes, such walls are necessary but they should always be temporary because after a while they cease to offer comfort and security and, instead, become prisons of our own making.

In these psychic jails, everyone on the outside becomes a threat. The threat is "other", all that is "not me". But who or what is "other" and why do humans have a tendency to reject difference? In part, the reasons for our fear are evolutionary, developed to help our species survive at a time when belonging to a tribe made our survival more likely.

Fear is an early warning system that flags up a potential threat and makes us alert, ready to run or stand and fight. But what if there is no real threat? What if the "threat" is all in our head or implanted by others and that what we actually fear is difference, the unfamiliar and the prospect of change?

Most of us struggle with change. Human beings are creatures of habit and, as such, we often turn away from the challenge and adaptations that change requires. Change demands that we think outside our usual cognitive realm, develop different neural pathways in order perform new tasks and to behave or think in ways that feel alien to us. This, in turn, can make us feel vulnerable and frustrated. Usually, though, after a bit of thrashing around, most of us adapt and often thrive in the process of change.

But when the fear of change is extreme – as in the case of the would-be assassin from Montana – it is easy to objectify "other" into a species that is devoid of humanness. In doing so, we open up a loveless one-way track whose terminus is the land of xenophobia. It's a place of destruction, hate and frothing rage and not easy to find a way back from.

The only way out is to become aware not just of the differences, but also the similarities between ourselves and others. When we recognise and feel the essential humanness of the other, we empathise with them.

Our empathy is a very human shield against carrying out violent and destructive acts upon others. The pain of a mother who loses a child as a result of war or illness, has the same depth of loss whether she happens to live in Aleppo or Arkansas. The hurt you feel when your friend or partner betrays you is the same, regardless of the colour of your skin. And the joy you feel when something really good happens in your life, has the same intensity for a Christian as it has for a Muslim.

These are the similarities that bind us, that humanise us but also protect us from the real threat, which lies in using anger and hate as a defence against our own fear of difference and change.