The Emperor Napoleon could be spinning in his tomb. So might be Admiral Pierre-Charles-Jean-Baptiste-Silvestre de Villeneuve, the man who lost the battle of Trafalgar.
In 2005, precisely two centuries after the battle, the French Government took the first of a series of decisions that led accidentally to the French taxpayer subsidising two giant warships for the Royal Navy.
The French Government's public spending watchdog protested this week that a defence co-operation agreement signed by Jacques Chirac and Tony Blair in 2006 led to a French contribution pure and simple to the financing of two British aircraft carriers in their development phase.
The amount of the accidental cross-Channel subsidy to HMS Queen Elizabeth and HMS Prince of Wales, now under construction on the Firth of Forth, is estimated as at least 100 million ($164 million) and possibly more than double that. The loss was buried at sea in the small print of the 2013 French defence estimates but dredged from its watery grave by the Cour des Comptes, or court of auditors, in its report this week.
Despite this experience, France and Britain are pushing ahead with ambitious plans for defence co-operation in other areas. David Cameron and President Francois Hollande signed another memorandum last month to develop a Franco-British pilotless fighter plane.