In some ways it is a law of nature. At regular intervals, buried under the crust of six decades of European building, the brutal realities of 'matchpolitik' re-emerge like lava, burning the cold slopes of a volcano in its stead. Some see these eruptions as a sign of vitality, others as a threat. They are in fact both these things.
Though the eruptions are certainly not a new occurrence, their frequency has intensified in recent years. They mark the biggest transformation in European political geography since 1953. The fall of the Berlin wall disrupted the political balance on the continent, that much is clear. But today it seems that the European Union's system is finding a new centre of gravity. It is no longer located in Strasbourg - the symbol of the Franco-German alliance, and the geographic centre of the former Western block, as well as the increasingly contested HQ of the European parliament. The EU's new centre of gravity is somewhere in Germany.
The €1,000 billion budget negotiations - ie the EU's budget for the period 2014-2020 - which were put on hold last week after 24 hours of discussions was evidence of this. Berlin was the conciliating party, stuck between, on the one hand, rich and thrifty north, of which it is both the first representative and the moderator; and on the other hand, crisis-struck south, and central Europe, the main beneficiary of the funds in question. Angela Merkel left Berlin serene and returned just as serene - convinced she could bridge the €30 billion gap between the two sides.
Whatever the outcome of negotiations, Germany will emerge the winner for reasons that have nothing to do with Merkel's austere manner, and everything to do with the geographic location of the Federal Republic. Because this draft budget is the visible part of another structural movement: it marks the launch of a European infrastructure and industrial research policy worth tens of billions of euros.
When it comes to high-voltage lines or cross-border freight trains, chances are they are going through Germany. The densification of the market and of the European bloc's infrastructures automatically benefits the centre more than the periphery. As for research funds, it doesn't take a genius to guess that the most industrialised and technologically advanced country is most likely to attract them.
The few extra billions French President François Hollande may eventually manage to secure for his farmers cannot hide the relative decline of the Common Agricultural Policy - relentless since the Marrakech agreements in 1994.
From here on in, everything that reinforces 'Europe' - in the meaning of political building focused on the continent - also reinforces Germany's place in Europe.
The second lesson of this budget summit is that the British islands seem to be adrift. What is striking is not London's capacity for nuisance, but how little that matters nowadays. The British PM went back to London without being forced to resort to any threats. The British veto was devalued by the German tactic of a 26-party-agreement-if-Cameron-is-being-difficult. The German chancellor managed all at once to scare Cameron and to convince him to stay inside the gates of Europe, while taking on the task of defending the British discount - if the UK doesn't get one, neither does Germany...
But both parties know perfectly well that in the next few years they will reach a fork in the road. The time where, in response to the threat of a British 'no', the continent will reply 'if you wish so, just go' no longer seems so far away. And what is mostly posing will eventually turn into a self-fulfilling prophecy: the UK existing in the Union without a means of pressure would have a short shelf life, and past that expiry date the time would come to announce that 'the continent will be isolated'. The insular law would have reasserted itself.
Should we fear this revenge of geography? Not necessarily. The first European communities were born - in the Cold War - from a geopolitical imperative: the need to anchor Germany - its Eastern part severed. France was the anchorage. These were the early days of Europe, but it was later able to move away from the Westphalian model. It even went and invented itself a currency. Between history and geography, there is neither defeat nor victory, only dialectics. And for the moment, the European's volcano's crust is holding up rather well.