He was a mixed-race rasta from Colombia, and he was my partner washing dishes in a lower East Side restaurant on my first (fairly unsuccessful) illegal tour of duty in NYC.

You learn a lot washing dishes. When you’re at the bottom of the pile, you experience the petty nastiness of managerial power at its best.

Luckily, Pedro kept most of the kitchen stoned for most of the time, so managerial strops about dishstacking techniques became part of the background comedy and perks of the job at 120 degrees in the bowels of a NewYork kitchen in August.

To my right was a Mexican fellow who never spoke, but played football at break in the manner of Maradona, so we just called him Diego. To his right were the chefs, Fitz, Fitz and Murph,who were all black as the ace.

Together with me, we were the four Irish in the kitchen. Fitzgibbon, Fitzgerald and Murphy were proud to be `black Irish’. (The fact that I was the only white man in the kitchen – and an English-speaking one to boot – speaks volumes about my waiting skills.)

The story of the black Irish is a fascinating and disputed one. There are as many as five million blacks in the US with Irish surnames. From the poet Toni Morrison, to the Harvard academic Randall Kennedy, we all know about Cassius Clay’s white Irish grandmother and the countless other Fitzes, Murphs and Kellys.

Conventional white Irish-American lore suggests that the black Irish are all descended from freed slaves who took their white masters’ names. If the masters were Irish, then they ended up with Irish names.

This theory went unchallenged for many years, and it suited the white Irish-American narrative that doesn’t deal well with intermarrying with blacks. In recent years, other interpretations, based on urban American population records from the 1830s to 1860s, indicate something much more complex which has huge relevance to our understanding of our past and also the future.

The alternative theory suggests that a significant minority of Irish-speaking women who arrived in New York in the 1840s ended up on the game.

Figures from the New York police force reveal that the vast majority of prostitutes cautioned by the forerunner of the NYPD were ethnically described as Gaelic Irish. In the late 1850s, there was what the records call an `alarming rise’ in the number of mulattos in the Lower East Side.

Who were these kids? The alternative theory of the black Irish contends that these were the bastard offspring of white Irish whores and their black clients.

Records for intermarriage also indicate a surprising (when compared with subsequent experience) number of Irish women hitched up with black men. Could these white Irish women from New Ross and Macroom, from Kilkee and Ballina, be the greatgreat-grandmothers of the black Irish? Economics and lessons from economic history suggest that this may well be the case.

In every society, the social pecking order is a function of how much a person can earn.This is related to the skill level of the person and the relative scarcity of these skills. So, for example, a good carpenter can earn more in the building boom than a good doctor.

The freed blacks in the US were typically well-skilled tradesmen like coopers, carpenters and blacksmiths, because prior to their freedom, enlightened masters invested in their education and trade.They were therefore able to survive and thrive.

So by the 1840s, the freed slaves of the northern union states would have constituted a solid artisan class.Then the Irish arrived, at a rate of 1,000 a day, with no skills, many without the language and nothing to sell.

Being white wasn’t going to give you an advantage over a skilled black craftsman. Fairly rapidly, it became evident that one thing the Irish could sell was themselves – and for Irish women, that meant their bodies.

Because the black man was a better financial bet than the Irish indigent, many Irish women chose to marry the man with better prospects – the man who could provide for the kids and keep a roof over their heads.

This explains the rise in mulattos, and also seems a more plausible explanation for the existence of the black Irish than the master’s name from the freed slaves in the South, particularly since the southern plantations were largely Paddy-free zones.

The Wasp owners of plantations in the south were not renowned for employing Irish Catholics at any level, let alone as foremen.In fact,the southern expression `hillbilly’ comes from northern Irish Protestants who lived in the southern states and marched around the hills of Appalachia every 12th of July with effigies of King Billy.

Fást forward to today. The major lessons from the Irish `whores of New York’ is that mass global immigration from the third world to Europe and Ireland over the coming years will lead to a significant development in the sex industry, because precisely the same process will occur.

This year, 95 million children will be born in the world; 91 per cent of them will be born in the developing world, and they will want to emigrate. This movement of populations will lead to a dramatic shift in the relative price of labour.

We – the educated, skilled whites – will see our average wage per hour rise, while they – the under-educated, largely black and Asian immigrants – will experience the opposite.

When these young women arrive here, they will sell what they can. The sex industry will explode in Ireland. There will be a boom in every aspect of it, from pornography produced here to lap-dancing clubs to prostitution. And it will be based on cheapness. The women of the third world will end up as hookers, strippers and dancers all over Ireland.

The Irish appetite for the sex industry has been clearly evidenced by the relentless march of the lap-dancing club. All around the country, local GAA clubs are no longer celebrating victory in the local pub but in the local lap-dancing outfit, where Ukrainian girls get their kit off. Needless to say, the internet provides any number of platforms for this carry-on.

However, the major point is not the demand, but rather the supply of women. One of the laws of economics is that supply creates its own demand, and this will apply to the sex industry as much as it does to the mobile phone game. Before the supply of mobiles at a cheap price in 1990,there was no demand or yearning for them. The supply of cheap bodies to the sex industry will have the same effect.

Every time I pass a lost-looking immigrant girl at a bus stop, I thinkof the great-great-grannies of my black Irish mates from the kitchen – all those Marys, Kathleens and Noras who left this place with no ideawhat was about to happen to them.

By 2020, the sex industry will be thriving here, with all its attendant problems, and Dev’s time-honoured vista will have mutated into one of `lap-dancing at the crossroads’.