In 1870, as the Prussian army advanced on Paris, Ernest Renan, the French philosopher, observed sadly: “This misunderstanding can only get worse.”

That was one of the greatest prophetic understatements of history. The relationship between France and Germany was littered for the next 75 years with bullets, barbed-wire and graves.

For sixty years now, the two countries have officially been  friends – or more than friends. They have been diplomatic “besties”. They have been the indispensable “couple” at the heart of the European Union. They have been the “motor” which drove the creation of the EU and its most ambitious policies, from the single currency to borderless freedom of movement.

 Last Sunday President Emmanuel Macron and Chancellor Olaf Scholz and their entire governments met in Paris to commemorate the signing of the Elysée Treaty which officially ended Franco-German enmity on January 22nd 1963.

Macron spoke grandiloquently of the two countries as “two souls in one body”. Scholz said, more prosaically, that France and Germany were a “motor” whose fuel was not “flattery” but a “determination to convert controversy into common action”.

The two governments proceeded to agree on …not very much.

Last weekend’s inter-governmental meeting replaced a summit at Fontainebleau in October which was cancelled at the last moment by Macron after Paris and Berlin failed to end a string of quarrels about energy, anti-inflation subsidies and arms procurement.

A couple of those quarrels have since been patched up. Several remain poisonously unresolved, including a multi-billion-euro German plan to shield its industry from high energy prices. France says that this will damage competition in the European single market.

Paris wants Berlin to agree an EU-wide anti-inflation policy, backed by EU loans. Berlin refuses.

There have been many Franco-German quarrels in the last 60 years. The present crop are, arguably, no worse than those which have gone before.

What has changed is that Germany and France are weaker – Germany economically, France diplomatically.

Germany’s economic model (dependant on Russian gas and Chinese cooperation) has been undermined by the Ukraine war.

The status of the France-Germany as Europe’s “first couple” has been challenged by the perception – right or wrong – that the two countries placed too much confidence in Vladimir Putin before the Ukraine invasion and that they have been too faint in their support for Kyiv since.

The Russian invasion of Ukraine seemed, in one respect, to strengthen Macron’s argument that Europe should be able defend its own “sovereignty”, both militarily and  economically. It has also undermined it.

The importance of the US military commitment to Europe have been re-born. Eastern European and Baltic countries have asserted themselves. They have lost patience with France and Germany.

Franco-German agreements used to be essential to the running of the EU. They are now viewed, from the east, with some suspicion. As a result, a new generation of German diplomats and politicians – some not all – view the Paris-Berlin partnership as limiting or unnecessary.

The crisis has also coincided with the arrival of a new German Chancellor at the head of a quarrelsome Left-Green-centre coalition. Previously, French officials say, nothing could happen unless Angela Merkel agreed. Now, they say, nothing much happens even if Olaf Scholz is broadly on our side.

In a broader sense, the Franco-German post-war friendship has always been fragile.

The treaty signed at the Elysée Palace 60 years ago spoke of a “profound change in the relationship between the two peoples”.  But the “relationship” between the French and German peoples never matched the relationship between governments and political elites.

The old visceral enmity is largely gone but prejudices and generalisations still colour the view across the Rhine in both directions. The French see the Germans as disciplined, predictable, hard-working and humourless. The Germans see the French as charming, witty, superficial, arrogant, lazy and unreliable.

In the 19th century – and up to the middle of this century – the French and Germans fought and hated each other but remained fascinated by the culture of the other. Since the 1960s, the two governments have worked intimately together, but the two peoples have increasingly lost interest in each other.

Two anecdotes.

When my eldest son was 15, we hosted a party for his school friends and their German language exchanges. (The wooden floor in our Paris flat never recovered.)

The kids got on well but they spoke to each other only in English. The teaching of French in Germany and German and France has since all but collapsed.

Secondly, some years ago I caught a direct overnight train from Munich to Paris. By the time it crossed the Rhine, there were almost no German passengers. A new cast of French travellers boarded in Strasbourg. Instead of one train, it was two trains using the same carriages.

Two minor – but maybe not so minor – announcements were made after last weekend’s Franco-German summit. There will be 60,000 free rail tickets for young French and German people to visit one another’s countries this summer. The two governments have applied pressure on their rail companies to start a direct high-speed rail service between Paris and Berlin.

Both are excellent ideas. The glue of a broader, more popular friendship between the countries could be important in the 21^st century.

The Franco-German partnership, post-the Ukraine conflict in a 27-country EU and counting, will never again be as powerful and central as it was in circa 1970-2000. It remains crucial all the same. It is difficult to imagine that the EU  can thrive, or even survive, if the “couple” divorces or the “motor” goes into reverse gear.

The misunderstandings will continue. Lets hope they do not get worse.