We are all from somewhere. Why do we keep forgetting it?

I recently commissioned a mural for the wall of my company’s headquarters, Our Community House in North Melbourne.

I didn’t want another corporate logo. I wanted something that might make the thousands of people who walk, cycle and drive along Victoria Street every day stop, even for a moment, and think.

LING, the artist, came up with five words painted in enormous letters: WE ARE ALL FROM SOMEWHERE.

Adjacent are these words: “We live, love, stand by one another and pay respects on Aboriginal Land.”

It is a simple idea. But at this particular moment in Australia, perhaps it is one we need reminding of.

Sixty years ago, I grew up only a few streets away from where that wall is now.

Our neighbourhood was full of migrants. Italians, Chinese, Greeks and a rich diversity of people from other cultures lived and worked around us, many of them at the nearby Queen Victoria Market.

My father was Irish and my mother was English. And we were racist.

Not necessarily in the angry, organised way we think of racism today. It was often casual, thoughtless and completely normalised. As children we used words for our school buddies that I am ashamed of today – Ching-Chongs, Wogs, Dagos, Spags. We went to the local Catholic schools that supposedly taught us how to be good and proper people, while in the playground we divided the world into us and them.

The Irish knew something about being “them”. There was strong prejudice against Irish people. Signs saying “No Irish” were part of the local culture (unless Dad was heading to the pub) and discrimination was experienced by generations of Irish migrants here and elsewhere.

Yet yesterday’s outsider has an extraordinary capacity to become today’s insider, and then to look suspiciously at the next person coming through the door. That is what troubles me now. Australia is again having an argument about immigration, race and belonging. One Nation is attracting increasing support, even though it has no real policies other than to divide and vilify.

Anxiety about migration numbers is real, and there are perfectly legitimate debates to be had about population growth, housing, infrastructure and whether governments are properly planning for the number of people arriving. But something ugly can happen when a debate about numbers becomes a debate about people. Migrants stop being neighbours, workmates, doctors, cleaners, engineers, students, shopkeepers and children. They become “the problem”.

Why are we so mean? It is a question I genuinely struggle with.