The problem for Billy Hutchinson and the others trying to build a party for working-class Protestants is that they have not yet defined the distinct interests of the Protestant working class.

The main reason for this, in turn, is that when it comes to class, it is very difficult to see where a distinction can be found between, for example, the interests of the Short Strand and the interests of the Shankill.

There may be other distinctions, such as attitudes to flags and parades. But with regard to day-to-day economic matters, the people of the Short Strand and Shankill are in the same boat.

Maybe some have snaffled better berths than others – life's like that. But these days, it will have been individual aptitude for pushing and shoving, not badges of tribal identity, that will have made the difference.

It wasn't always this way. At the beginning of the Troubles in the late 1960s, there was nothing irrational about working-class Catholics believing that discrimination on account of religion was the reason for the economic ills that assailed them.

In truth, discrimination was by no means the only, or the most important, factor. Its role tended to be inflated for nefarious political purposes.

But the conviction was well-founded that winning better living conditions for poorly-off Catholic areas required a redistribution of resources, which could only be won through an assault on the system of governance.

Against that background, working-class Protestants were not being irrational in sensing that they were being set up to play the losers in this scenario.

Andy Tyrie, leader of the Ulster Defence Association in the early 1970s, summed it up in neat, if cliched, terms in his remark that, "Ordinary Prods looking down on ordinary Taigs is like tuppence ha'penny looking down on tuppence."

Pushed on this at a meeting in London in, I think, 1971, he elaborated, "When tuppence ha'penny is all you've got, the ha'penny looks a lot more." (Aside: at the same meeting I asked him why he always wore sunglasses, even indoors. "The thing is," he explained, "I don't look so sinister without them." I couldn't tell whether he was joking, on account of him having dark glasses on. They don't make loyalist leaders like Andy anymore).

Today, for practical purposes, the basis for the ha'penny difference has disappeared. There are exceptions. There always are. Housing in north Belfast remains entangled in sectarianism, the needs of Catholic families sacrificed to the sectarian interests of the DUP. But this is now an anomaly, not the norm. In most situations, Protestants are at least as likely as Catholics to be handed the short end of any stick. Being ground down has become a shared experience.

At its annual conference in Antrim last weekend, the Progressive Unionist Party put its credentials as a champion of working-class Protestants on display, passing resolutions demanding, for example, the protection of the NHS, the abolition of zero-hours contracts and an end to discrimination against women.

Other matters mentioned by party leader Billy Hutchinson over the weekend included opposition to welfare cuts and support for an increase in the minimum wage.

There are no solutions to any of these problems in Protestant areas which would not also be solutions in Catholic areas. There are distinct class interests in all of the issues, but distinct Catholic or Protestant interests in none of them.

We need separate parties in each community fighting separately for working-class interests like we need a hole in the head. Or, to put it another way, a party setting out to represent the plain people of one community only cannot accurately reflect the interests of the plain people of any community.

The PUP does not have the wriggle room enjoyed by Sinn Fein, whose support guarantees it a place in a system of government that allows it to be in opposition at the same time, representing the institutions of state while playacting on the barricades. Sinn Fein can style itself a party of class while at the same time ignoring class altogether to assert leadership of its 'own' community.

The PUP has neither the bulk nor the agility to pull this off. The party will survive and, in the short-term, may even prosper. It is blessed in the fact that its mainstream unionist rivals are led by dunderheads.

But supporters of the PUP who genuinely see themselves as leftists will discover – as in the fullness of time will supporters of Sinn Fein – that the differences between class and communal politics are not matters of style, or accent, but are fundamental and, in the end, irreconcilable.

Belfast Telegraph