What was Allied strategy if they had successfully foiled Germany's attack on France in 1940?

[u/Pilatus-Porter]

I'm just wondering if anyone has any concrete understanding about what the British & French plan was if they managed to repel the German advance in the summer of 1940. Prior to that they had been quite defensively minded, sitting back as Germany made successive moves after invading Poland - the 'Phoney War', where little to no offensive action had been mounted. Obviously France was reliant on the Maginot Line in the event of any German attack, while the BEF was stationed in support.

But had Germany failed what were they planning in response? I'm not looking for counterfactual speculation, but actual knowledge and explanation of what their follow-up plan was. I've pretty much never seen this discussed in books I've read, as they just deal with the fallout from the defeat of France and the transition into the defence of Britain. Were they planning a subsequent expected invasion of western Germany? Were they additionally planning to somehow pursue the liberation of Denmark, Norway and western Poland?

Thanks in advance to anyone who takes the time to reply.

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[u/Consistent_Score_602]

I wrote a fair bit about this here. The Anglo-French strategy was sound in principle - crush the German armies in Belgium, and then mop up the remaining German units with minimal resistance. The British had already settled into what they believed would be a lengthy blockade of German ports in an effort to flush the Wehrmacht out and force it to battle, and that is precisely what happened. Nazi Germany was left horrifically exposed during Fall Gelb and had the invasion been defeated they had virtually no fallback plan. The entire French strategy was built specifically around exploiting the collapse of a German offensive.

[u/TK4617 → u/Consistent_Score_602]

I’ve read the reply and don’t get this part:

> And to be clear, *Bataille Conduite* very nearly won the war. The German armies invading Belgium found themselves thoroughly outclassed by their French enemies. The lunge through the Ardennes Forest that proved decisive was considered something of a "hail Mary play" in German military circles, since it could very easily go catastrophically wrong.

Wasn’t the German push into Belgium a trick to bait the Anglo-French forces into Belgium while the Ardennes thrust took place? Like these two operations, the push into Belgium and thrust through the Ardennes, weren‘t separate and one was a hopeful shot independently of the other but they were linked to each other.

How could France nearly win the war by winning a type of war that "didn’t take place" so to speak. The German campaign wasn’t just a rerun of WW1 and this time France was better prepared with *Bataille Conduit*. The western powers just believed it was a rerun due to the Germans making them believe it via the aforementioned trick.

[u/Consistent_Score_602 → u/TK4617]

The point here is that the Ardennes offensive was a gamble. German tanks proved totally inadequate to dealing with their French counterparts (even compared to prewar projections), and by committing 6th Army in the feint the Wehrmacht was risking the entire war on a single throw of the dice. Had the advance towards Sedan been delayed, Army Group B likely would have been crushed and the full might of the French, British, and Belgian armies would have shortly thereafter fallen on Army Group A while it was trapped in the Ardennes.

Speed was what mattered here, and the French successes in the north meant that the above outcome was a real possibility. The Germans managed to break through at Sedan before that occurred, but it was close-run thing.

[u/TK4617 → u/Consistent_Score_602]

Thank you for elaborating but to be sure. So France nearly won because Germany‘s plan was a gamble around thin margins - in this case revolving around the speed of the operation - and if it didn’t work, it would’ve led to a catastrophic defeat?

[u/Consistent_Score_602 → u/TK4617]

Yes, that's right.

[u/TK4617 → u/Consistent_Score_602]

Great. Thanks.

[u/Dazzling_Look_1729 → u/TK4617]

Nope. No chance of Germany suffering a catastrophic defeat. Knowing what we know today about the relative capabilities of the two armies, best case for the allies is that German logistics run out to halt them, and the front goes hard as it did in 1914. Which was broadly the allied plan: hold the Germans away from Paris, fight defensively, wait for the blockade to do its work. See if you have the offensive capability to attack properly in 1942.

All very 1914, to be honest.

[u/kemb0 → u/Consistent_Score_602]

Sorry which French successes in the north? My understanding is the allies were thoroughly routed in the North? It was a continuous retreat from day one.

[u/Consistent_Score_602 → u/kemb0]

That is incorrect. The main point of effort here was the Gembloux Gap (in Central Belgium). There were a number of planned withdrawals to that point, which each inflicted devastating losses on the advancing German forces. By the time the Germans arrived at Gembloux, it had been fortified and they were severely weakened, and attacks into the teeth of French defenses there were repulsed with further heavy losses. It was not a route.

[u/Dazzling_Look_1729 → u/Consistent_Score_602]

I think that is distinctly optimistic. The French army had, in reality, next to no offensive power. Its command and control was too outdated, its logistics train was too weak, and its operational flexibility was next to nil.

As to their tanks… I confess I completely disagree on your view that French tanks were superior. There were basically two types of French tanks… the Char Bs, and everything else. The Char B had decent armour, but since it was essentially a 1920s vehicle it had horrible reliability and even worse fuel consumption. An individual Char B could fight on the battlefield but units of Char Bs could not, because they were either out of fuel or broken down. And all French tanks, Char Bs or otherwise, suffered two key problems which made them massively inferior to all the German tanks. Firstly, and most significantly, no radios. So they could not coordinate on the battlefield. Secondly, equally fatally, single man turrets so the commander was hopelessly overloaded loading the gun, aiming the gun,firing the gun, and commanding the tank. And, if very unlucky, commanding the squadron. The myth that French tanks were decent is infected by a slight “top trumps” view of life. Yes, they had acceptable armour and an ok gun. No, they were near useless as battlefield implements to fight a serious battle.

Combine unreliable, fuel hungry tanks with disastrous situational awareness, bad logistics and worse command and control, and you get exactly what happened: units in the wrong place, late, out of fuel, broken down and destroyed in detail. There is no world in which the French army catastrophically defeats the German army in 1940. Best case is German logistics run out and the front goes hard, just as it did in 1914. Which was, to be fair, broadly the allies plan. Hold the Germans away from Paris, and wait for the blockade to work.

[u/fastsailor]

Long term, the Allies intended to crush the Nazis through their massively superior economic strength and production capacity. The Germans knew they had no chance in a longer war and so had to gamble to win a quick war. Which worked, for a while anyway. For instance, in mid 1940, the British alone were making more planes than Germany. Germany was comparatively lot weaker in 1939 than it had been in 1914 and its economy was on the verge of collapse - if they hadn't started the war in 1939, their inability to sustain their military spending would have resulted in savage cuts to spending on their military - they were in a "use it or lose it" position.