Re. when criticizing the French military we need to remember how the geography makes France so difficult to defend. Not the geography. The leadership just wasn't committed.
WW1. One of the take-aways from the "Guns of August" is that the French wanted WW1 as much as the Germans. The French were planning to strike into the S of Germany and drive all the way to Berlin. They saw that the Germans were moving forces N to attack into France on an axis well N of their own planned attack and they were good with that. They reasoned that every German unit that got pulled N made their sector weaker. The French weren't too interested in moving their own forces N to counter the Germans. They were all about audacity. They didn't need artillery because of "audacity". They didn't need logistical support because "audacity".
Because the French were in the S and the Germans were in the N. ~80% of the French Army faced about 10% of the German Army. On the first day of the French attach, they pushed about 10km into Germany. On the 2nd day they were thrown back. But we never hear about this, because WW1 is all about German aggression.
Pre WW2. A couple years ago I listened to the 3 volume Churchill biography by Manchester. It's a fascinating look at the Brits from Victorian times to the 50's. I learned a lot. One of the interesting take-aways was all the opportunities that the French and Brits had to stop Hitler prior to him become a real threat. Apparently there were numerous times when either German politics or German generals would take him down, as soon as he over-reached. But he didn't over-reach. The French and, to a lesser extent the Brits, backed down each time. An example is the Rhineland, a sizable region between Germany and France that was demilitarized after WW1. The German generals were just sure that if Hitler carried out his plan, France would march into the Rhineland and set things to rights, and the German generals would use the resulting loss of face to take down Hitler and shoot him.
But, to the enormous aggravation of the German generals, Hitler's mad plan to march troops into the demilitarized Rhineland succeeded. The Germans marched in some token force and the million strong French Army, instead of using some of that audacity, wrung their hands and wanted to consult with the Brits on the issue for a couple months. So one more win cemented Hitler's power.
WW2. Still drawing from the Manchester book...recall that the invasion of France was totally predictable. A state of war already existed after Germany invaded Poland. But even in the final months before Germany attacked Poland, France was still selling heavy artillery and tanks to customers around the world, instead of keeping them for their own use. The French leadership was never serious. The French had a bigger Army and in some important areas, better equipment. And they got steamrolled. That's not the fault of the guys at the pointy end, that's a leadership problem.
If you read about the battle of Stalingrad, you'll read about some Russian Infantry platoon that was holed up in some stout building at the edge of no-mans land. The Germans attacked that building over and over again and the platoon did serious damage to the Germans. That single platoon of Russians, prob 20 dudes, were responsible for more German casualties then the French caused in the defense of Paris.
That said. I've worked a bit with the French Foreign legion. Those guys are hard SOBs.
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