Both the German chancellor and French president Emmanuel Macron were in solemn attendance while their respective countries – the power couple of European politics - renewed and upgraded their marriage vows originally made with the Elysee treaty of 1963.

A new Franco-German treaty committed them to, among other things, closer consultations to develop joint positions ahead of important EU meetings, a Franco-German economic area with joint rules, tighter military cooperation and support for Germany's permanent membership of the United Nations Security Council.

This last pledge reveals a long-term risk inherent in the new treaty: that the Franco-German couple, no longer the engine of a much-enlarged EU, might become a vehicle for the reassertion of two strong national sovereignties, as opposed to the linchpin of a European federal order.

It is true that the unwillingness to convert France's permanent seat into a European one has come, as usual, from Paris.

Still last November Berlin's finance minister Olaf Scholz had proposed that in the medium term the French seat might become an EU seat, provoking the dry French rebuke that this would run counter to the UN charter (what a compelling political argument!).

Apart from the traditional intergovernmental leanings of the French Gaullist tradition – which clearly lurk just beneath the surface of Macron's much-flaunted European-ism – it is however the evolution of Germany under Merkel that is interesting.

Merkel's measured leadership in the EU during the last decade of multiple crises seems to have reconstituted Germany as a strong national state that, while committed to European cooperation, has little appetite for dissolving itself in a supranational political union.

From Kohl to Merkel

This is a crucial change from the Helmut Kohl era, when the attainment of a European federation seemed to be at hand and was clearly the favoured option of German elites.

The recovery of the eastern protestant regions after reunification meant that the post-war dominance of the catholic south and west – historically more cosmopolitan and federative in outlook – has been undermined.

More recently, the experience of successful, albeit contested, continental leadership has also made Germans more outward-looking and self-conscious in European and global power games.

The country can rightly pride itself with having kept the EU together thanks to its impeccable economic performance and renewed sense of national purpose.

These trends have been compounded by Merkel's essentially intergovernmental vision of European integration.

The last federative effort of German elites was the EU's ill-fated constitutional treaty, initiated by a famous speech of Joschka Fischer at the Humboldt University in 2000.

Ever since Merkel took over, her specific brand of inter-governmentalism has left its mark on any new European initiative, most notably during the sovereign debt crisis and the management of financial assistance to the EU's periphery.

Bismarck 2.0

With all appropriate caveats, it is perhaps not excessive to characterise the result as neo-Bismarckian: the reconstitution of Germany as a strong national state that is again trotting in the wilderness of history exposed to all the winds of change without strong continental safeguards.

In the long-term, Merkel's responsible leadership and her commitment to multilateralism and European cooperation seems little more than the modern equivalent of Bismarck's alliance system: a passing safeguard dangerously dependent on the wisdom of her successors.

Only time will tell, but in the very different context of the 21st century, Merkel may have unwittingly revitalised what Bismarck had achieved and Hitler destroyed: a self-restrained but conscious and confident German national state.

It is perhaps no accident that this period saw the rebirth of a nationalist right in Germany.

The chancellor restored the German nation to a rank that it had never had in Europe since the 1930s and turned the prospect of a European federal union into a remote regulative ideal.

The 'Cunning of Reason' of which Hegel spoke is always at work in history.

Those who today contest her in the name of a Europe of nations cooperating with each other may one day realise that she did far more than them to achieve it.