We're at a point now where Brexit debate in the UK is almost completely detached from political debate in the EU.

Does Brexit even mean Brexit anymore?

Or does it now have a purely symbolic function in a zero sum battle between British elite factions?

What is the EU supposed to do with a society that is on the brink of plunging into elite polarisation that opens up a high risk of British state paralysis? How does the EU contain the fallout from internal UK divisions and prevent a disorderly break-up of the UK?

In the run up to the Article 50 extension deadline what can the EU do to provide rival UK elite factions with off ramps through which the British state can climb down from the untenable position it has placed itself in?

If No Deal happens, how quickly can the EU place an interim treaty mimicking the Withdrawal Agreement and transition to 2027 in front of a UK government trying to avoid a disorderly breakup of the UK state? How quickly can such a mixed treaty be rammed through EU27 parliaments?

If London mishandles No Deal in a way the leads to radicalisation within English elites, and a serious move in Scotland or NI to break away, how does the EU respond to the ambitions of such proto-states to align with the EU system? How does the EU manage Welsh concerns?

If a UK drifts towards disorderly break-up, how do the EU and NATO handle the fallout when it comes to the weakening of the UK's ability to secure Europe and America's Northern and Atlantic flanks? What happens to early warning systems against Russian aircraft or naval vessels?

If EU and NATO face serious weakening of the UK state, how will the future of the British nuclear deterrent be handled? Who replaces British troops in deployment areas if the UK military comes under pressure at home? How would disorderly break-up of the UK affect bond markets?

The potential destabilising effects of a UK state crisis for the EU and NATO need to be examined now. Developing responses to potential worst case scenarios for the future of the UK state would enable the EU and NATO to mitigate them or even head them off.

For all the talk of "black swans", it's more often than not the known knowns that no one really wants to admit knowing that create the foundations for the next big crisis everyone claims they never saw coming.