‘What is grave about this situation, Messieurs, is that it is not serious’, was how General de Gaulle addressed his cabinet following the attempted putsch des généraux in April 1961. That could equally apply to recent Franco-British ructions over fishing rights in the Channel Islands. It is mere gesture politics, for all the French retaliatory threats to cut off the electricity supply to Jersey, the British dispatch of two Royal Navy vessels and the French countering with two patrol boats. Behind the facade France and Britain are serious military and diplomatic allies bound by important and wide-ranging security treaties that go beyond just Nato. But it is the French who have the most to lose were relations between Paris and London to deteriorate beyond the cosmetic.

Governments and regimes come and go, but a state’s foreign policy varies little for the simple reason that it is founded on geography and immutable geostrategic national interests. General de Gaulle never ceased calling ‘Russia’ by that name, even when it was the USSR, precisely because it was the same entity with at heart the same geostrategic interests. In that he was following the line of the great 19th century British foreign secretary, Lord Palmerston, when he reminded parliament that: ‘we have no eternal allies, and we have no perpetual enemies. Our interests are eternal and perpetual and those interests it is our duty to follow.’

Britain’s geostrategic interest is the open sea, international commerce and no hegemonic power in continental Europe. France shares the British fear of a hegemonic power in Europe — other than its own — whether it be 17th century Spain, 18th century Austria or, since 1871, Germany, whose unification was sealed on the back of French defeat.

Subsequently, France looked to Britain as a counterweight to a dominant Germany constantly seeking an elusive binding peacetime military alliance with London. Disappointed in that quest, post-Suez France accelerated the alternative strategy for constraining German power: binding her ever more tightly in the French-controlled web of European integration, as I argued on Coffee House a year ago.

For as long as Germany was willing to play the game and pretend not to be powerful the European project satisfied France’s vital interests. When on occasions Germany forsook her submissive role, at least after 1973 Paris could seek allegiance from Britain as a counterweight. But ever-ascending German economic, financial and, increasingly, political power lays bare France’s relative decline in the EU. Now that Britain has left, France is cheek by jowl with Germany and fully conscious that her perpetual interest of denying a European hegemon is threatened.

President Macron’s risky strategy of accelerating the process of ever-deeper European integration has the advantage of denying Germany (but also France) sovereignty: the same Faustian pact that President Mitterrand sealed in Maastricht, fearful of the long-term consequences of German reunification after 1989. But the risk — as many in France know — is that continued French economic and financial decline will further loosen Paris’s grip on the EU while tightening Berlin’s. Germany risks becoming — reluctantly — the natural European hegemon that France has always feared.

The one significant domain where France has the upper hand over Germany is in the military and international fields, by dint of nuclear weapons, reactive and combatant armed forces and a permanent seat on the UN Security Council, none of which Germany has. In this France is similar to Britain. The century-old military association with Britain, albeit not a formal peacetime alliance, is a French force multiplier and insurance policy. Hence in recent times, the 1998 Saint-Malo declaration and the 2010 Lancaster House agreement both seriously irked Berlin.

This is why Paris has more to lose than London from a serious deterioration of their relations. Without this force multiplier, France would be hobbled internationally and eventually have little alternative but to throw her military lot in with Germany and the ‘political dwarf and military worm’ that is the EU. However much Macron might call for a European army he knows this will not happen in the next ten years, if ever.

Even Macron knows that it is in France’s ‘vital’ interest to maintain tight defence and security relations with Britain, as the most recent French defence white paper explicitly states. This is why — regardless of Brexit — Britain looms so large in Macron’s 2017 grand strategic review that seeks to pivot to the Indo-Pacific and why Macron was so looking forward to celebrating the tenth anniversary of the Lancaster House agreement last year.

That treaty goes further on defence and security partnership (including nuclear weapons, advanced arms construction, joint force projection) than with any other European power. An example of this is Britain’s frontline support to France with heavy-lift helicopter capacity and crewing in the Sahel, where EU support is minimal. There is no way France would wish to jeopardise this strategic support and long term insurance policy.

It is always a popular pastime on both sides of the Channel to do some English or French bashing for domestic political reasons. But Paris should be reminded not to overstep the mark. Britain has not leveraged the Lancaster House agreement in any visible way but France is building up a lot of political debt. London should call in that debt soon.