David Trimble has many qualities but spreading sweetness and light is not prominent among them. He has pricked the bubble of the GFA commemorations with a sinister warning.

The one thing that would provoke loyalist paramilitaries is the present Irish government saying silly things about the border and the constitutional issue. If it looks as though the constitutional arrangements of the agreement, based on the principle of consent, are going to be superseded by so-called ‘special EU status’ then that is going to weaken the union and undermine the very agreement that Dublin says it wants to uphold.

Note that his criticism is not focused on comments from Simon Coveney and Leo Varadkar about their highly qualified aspiration for a united Ireland in their lifetimes. Rather, it rests on what used to be known as special status for Northern Ireland to remain within the single market and customs union but which now has developed into the famous option 3, the backstop of the draft agreement. This is what the UK signed up to with EU 27 as a contingency against the failure of the Brexit negotiations, but hopes, indeed insists, it will not happen.

Oddly for the pedantic lawyer that he is, Trimble bases his warning on a piece of Brussels gossip.

“I believe that some senior Irish government officials go around Brussels talking about the ‘Hong Kong model’ – the one country, two systems idea,” Trimble said. “That is a precedent they talk about where sovereignty has been transferred from Britain to China. Anything that looks remotely like this or is building on that foundation would be extremely dangerous. Although I think that under this Conservative government I cannot see that prevailing.”

That would be more like the Sinn Fein model than anything else. Here Trimble seems to be expressing a fundamental if not universal unionist opinion, that a continuation of an- all island economy under EU rules amounts to a constitutional change that could lead to Irish unity without the explicit consent of the people. Economically and socially, it would be no more than the continuation of today’s status quo within the GFA and common membership of the EU. To my knowledge, although he was no enthusiast for the north-south bodies, he never stigmatised them as Irish unity by the back door.

But UK withdrawal from the EU makes all the difference and changes everything it seems. Any move to differentiate Northern Ireland from the rest of the UK would be unconstitutional. Interestingly he has so far omitted to criticise the British government for entertaining the idea of the backstop even hypothetically, reserving his ire for the Irish government.

While he criticises the DUP for obstructing same sex marriage and putting a price on propping up the Conservative government, Trimble appears to share with them a view that has never fully been put into words: that they would prefer Northern Ireland to be poorer well detached from the EU than closely associated with the Republic remaining within it.

This would explain the basic Leave reflex that to begin with did not seem to dominate mainstream unionist thinking but in the end won out ; that is, stick with England’s view of the UK’s interests at all costs as a strategy for preserving the Union. This a perfect zero sum attitude which many people including many unionists must be praying will become irrelevant as a result of successful Brexit negotiations. It is also of doubtful relevance as it is self determination in both parts of Ireland not Great Britain that will determine the Union’s future.

There are indeed valid concerns about the Irish government’s authority to represent the rights of Irish citizens within Northern Ireland within a necessarily revised British-Irish relationship after Brexit. These have yet to be addressed. But for Trimble to raise the spectre of provoked loyalist paramilitaries is unworthy of him. All it will do is to harden attitudes and put nationalists on their high horses.