In the political Groundhog Day that is Brexit, we have been told that "crunch time" is just around the corner on so many separate occasions that the word has lost practically all meaning. This week, though, the crunchiest crunch time yet has presented itself.
Our government’s very existence is predicated on the set-in-stone Brexit date of 31 October, and the final EU Council summit before that date is a mere three days away. If a Brexit deal is not reached imminently, the prime minister will either take us out without a deal or be replaced by another who would pursue a referendum. The deal, then, is now or never.
The sticking point, of course, is the Irish border. Many thousands of words have been written by pundits of all shapes and sizes about the technical difficulty of the post-Brexit customs situation on the island of Ireland; despite that, nobody understands it, no matter what they say.
As negotiators hash out the details and desperately try to bridge the gap – both metaphorically and, perhaps, literally – between Britain and Ireland, we have all become tremendously well-versed in why this matters for the UK but remain broadly oblivious of its immense significance for the European project.
For the first time ever, next month will see a border being created between the EU and the rest of the world. That Irish customs arrangements have become the stumbling block over which the Brexit horse has very dramatically tumbled is indicative of the conflict between local and continental politics.
The Good Friday Agreement and the persistent fragility of the status quo in Northern Ireland, against the backdrop of a history marred with conflict and violence, provide an extremely uncomfortable setting upon which to negotiate a new political relationship. The European supra-state is having great difficulty maintaining the integrity of its union in this area as a result.
This cuts to the heart of what the EU is. For Brussels, the Irish border question is an existential issue. The European project, couched in fluffy words like union and integration, necessitates in practice the sweeping centralisation of powers such that bureaucrats in Belgium can remotely govern vast swathes of the continent.
By far the most disquieting aspect of the Brexit debacle from a European perspective, is that it demonstrates just how difficult it is for the EU to co-exist in close quarters with other major economies.
It is becoming inescapably clear just how difficult it is to achieve a true European Union when a member (Ireland) and a non-member (the UK) have such a fraught relationship and happen to be next-door neighbours. The Greek crisis tested the European financial union to its extremes, and it survived, albeit at considerable cost. The Irish border question will similarly push the political union to its limits, and perhaps beyond.
If the EU is to survive Brexit with its grand dream intact, it must demonstrate that it is capable of reconciling its desire for supra-state governance with complex domestic politics by reaching a deal with the British government. The Irish border question is by far the toughest test of its core principles in its history.
In this sense, the UK has much less to lose than Brussels if the talks fail. While incessant and riled public discourse has made us all very aware indeed of the consequences of a no-deal exit for Britain, the continent has refused to confront the existential doom it faces if it proves incapable of finding a Brexit deal that is acceptable to Britain.
No deal talk on both sides of the Channel has focussed on the immediate and material consequences of crashing out of a single market and customs union. This makes sense for the UK, but for Brussels, it is myopic in the extreme. The EU is apparently hoping that the rest of us do not notice that it is facing this existential crisis.
While a no-deal exit would constitute a minor failure for the British government, it would be nothing less than a catastrophe for Europe; not because of the customs implications, but because of what it would say about the viability and longevity of the ever-expanding European project.
If the EU cannot find a way to coexist with the UK on the island of Ireland, it will become clear that its peak is passed, and this is the beginning of the end of the EU.