In response, France wants “European strategic autonomy” and “European sovereignty”, Mr. Macron’s favorite phrases, to become a reality.

The case for a united Europe to chart its own course – after the submarine fiasco, after the Afghan chaos, after President Donald J. Trump’s contempt for Europe, after Brexit and in light of the clear transatlantic differences over China – could hardly be more solid. For Mr. Le Drian, echoing Mr. Macron, this is the only way for Europe to “remain in history”.

The problem is that the European Union is disunited. The affront to France has on the whole met with resounding silence from her European allies, although Ursula von der Leyen, the president of the European Commission, the executive body of the European Union, told CNN that “one of our member states has been treated in a way that is not acceptable.

Mr. Le Drian has spoken to his German counterpart, Heiko Maas, but Germany’s American connection implies nothing less than the country’s post-war renaissance, something unshakable.

As for the countries of Central Europe like Poland and Hungary, they place American protection through NATO well above French interests in the Indo-Pacific. For them, European “sovereignty” is anathema; they want theirs, stolen not so long ago by the Soviet Union.

Since the European Union’s foreign policy decisions must be taken unanimously, these differences are very important.

“The agreement on submarines has strengthened the validity of Mr. Macron’s plea,” said Dominique Moisi, a political scientist, referring to the president’s quest for a much stronger and more autonomous Europe. “It also reinforced Mr. Macron’s loneliness. We are right, but we are alone.