Jon Tonge: Is the Good Friday Agreement even still alive
The only surprise about Arlene Foster saying the Good Friday Agreement is 'not sacrosanct' is that people were surprised.
The 1998 deal has always been the agreement that dare not speak its name in DUP circles. Whilst 71% of Northern Ireland's voters were saying 'yes' in 1998, 70% of DUP members were voting 'no'.
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And more than a decade-and-a-half later, almost three-quarters of the DUP membership said they would vote no again, in the event of another referendum on the Good Friday Agreement.
Arlene Foster jumped from the pro-Agreement UUP to the DUP partly because she was never comfortable with the deal. So those startled by her utterances must be suffering from amnesia.
The DUP's conversion to tacit - but never avowed - support for the Good Friday Agreement was only on the basis that Ian Paisley wanted to be First Minister.
So, hey presto, the rules were changed at St Andrews in 2006 - with the subtlety of a sledgehammer - to allow the largest party in the largest designation - the DUP, funnily enough - to nominate for that post, without anything as troubling as cross-community approval being required. Most of the other changes at St Andrews - with the notable exception of Sinn Fein's movement towards supporting the PSNI - were minor. They involved such items as the introduction of a ministerial code to improve governance. That's gone well.
Foster is correct in claiming that the rules of the Good Friday Agreement are not written in stone.
Some of the Northern Ireland Act 1998 was replaced by new legislation after St Andrews.
However, those changes related mainly to internal power-sharing arrangements within Northern Ireland, updating the multi-party agreement reached in 1998.
The Good Friday Agreement is also an inter-state treaty between Britain and Ireland registered at the United Nations. Some breaches of the Good Friday Agreement are inevitable as a consequence of Brexit - which is backed by two-thirds of DUP voters.
Strand 2 of the Agreement requires the North-South Ministerial Council to take account of EU policies, implement them as appropriate and be represented at EU meetings. Is that really possible when one half of the Council will be outside of the EU from next March?
Ask a UK government minister - I have - what is proposed in respect of these redundant text sections of Strand 2 - and you get a shrug.
They have no idea - and it's not even clear that they truly care.
And the Irish government - 94% yes vote in the Republic in 1998 remember - is hardly going to start producing a new agreement to help the British take account of changed realities. So perhaps both governments will simply pretend they haven't noticed those awkward sections of the Agreement that no longer make sense.
Strands 1 and 3 of the Good Friday Agreement are less directly affected, but the right of citizens in Northern Ireland to full Irish citizenship is compromised by that citizenship being beyond the EU.
The bigger question raised by Foster is perhaps not whether the Good Friday Agreement is sacrosanct but whether it is alive. Devolved power-sharing has collapsed. The North-South Ministerial Council is not meeting.
The British-Irish Council is in abeyance. That's three strands of a three-stranded agreement that are not working. So the Agreement is in serious trouble. But, as in 1998, we are not awash with alternatives.
- Jon Tonge is Professor of Politics at the University of Liverpool