At the time of Nazi invasion in May and June of 1940, the French army was considered one of the most powerful armies in the world and a bulwark that would certainly be able to stop the Nazi aggression. However, contrary to all expectations, the French army was defeated just six weeks after Hitler’s assault. This surprising failure was largely due to the lack of coordination and the emphasis of the French on defensive actions.Nazi attacked France through the Ardennes, a hilly and forested location, where the Allies were not likely to expect an attack (Jackson 31). Their plan was to use their characteristic blitzkrieg (“lightning war”) technique. It is remarkable that the Allies had approximately 1, 000 more tanks than the Nazi at the beginning of the invasion (Sheffield). However, those of the tanks that could rival with German armoured formations, were largely dispersed, in contrast to the concentration of the German tanks. Therefore, the French overlooked the principle of massing combat power in space, which is crucial to overwhelm and dominate over the enemy (Principle 3). When the German air raid started on 10 May, 1940, attacked Holland and Belgium joined the Allies. However, instead of reinforcing them, this complicated the command and coordination (Sheffield). Moreover, as France had been almost isolated by 1939, the French government did not manage to coordinate the military operations efficiently with the Allies. Hence, there was no unity of command, which is an essential principle of war and operations (Principle 6). Having captured the Belgian Eban Emael fort, the Germans seized the initiative right away. While the Germans placed priority of flexibility and mobility, the French emphasized defensive action and the strength of firepower (Guan). Therefore, the French did not observe the principle of offensive (Principle 2). Moreover, by advancing to Low Countries they acted in a manner that was expected by Hitler and thus they violated the principle of surprise, which was consistently used by the Nazi (Principle 8).
While odds in this fight were in favor of the French, they were forced to surrender due to their lack of coordination and unity, emphasis on defense, inefficient mass concentration and failure to exploit the element of surprise. Though the French raised numerous counterattacks, they were weak and indecisive. As a result, the fighting spirit of the French was soon exhausted, which contributed to their failure.