Unlike prostrate China, France of the late 1930s enjoyed unequivocal status as one of the great powers. Expert opinion on military matters held that the French army, steeped in traditions of Napoleonic glory, and latterly confirmed by steadfastness (at the Marne, Verdun, Somme), was the world's finest. In contrast with Chiang's enervated forces and doubtful officer corps, France's confident soldiers were led by Great War heroes, not least of whom were Generals Maurice Gustave Gamelin and Maxime Weygand. The system of modern fortresses and barriers, running along French frontiers from Switzerland to Belgium, was of unexcelled design. This promised national safety at a casualty rate far below the numbing totals of 1914–1918, 4.5 to 5 million killed or wounded. Premised on the superiority of defense over offense, a lesson learned on the Western Front, the impregnable Maginot Line demonstrated France's inventiveness in military engineering, a species of genius dating to Marshal Vauban. The navy too was a formidable war machine, its ships, crews, and bases having benefited from attention lavished on them by Admiral Jean-François Darlan. Admittedly, France's air units might properly have numbered more bombers and fighters. Yet the high quality of French warplanes, arguably superior to anything manufactured in Germany, was generally thought to compensate for purported deficiencies in quantity. France, so responsible analysts testified, was guarded by men endowed with élan; they had at their disposal an arsenal bristling with armaments of the latest type and best caliber.

Virtually all Frenchmen, foreign observers too, including many in Berlin, were astonished in May–June 1940 by the rapidity of German victory, ratified on 22 June with the signing of an armistice in Compiègne. Two days later Mussolini also imposed a victor's peace that entailed territorial changes to Italy's advantage. Marc Bloch, medievalist and reserve army officer, lamented: “We have just suffered such a defeat as no one would have believed possible.” The novelist Irène Némirovsky wrote anxiously about the sudden birth of a disjointed world. Simone de Beauvoir, social theorist, noted this physiognomy in her newly occupied Paris: “Victory was written across every German face, while every French face proclaimed defeat aloud.”