>>17840153Had Belgium not canceled her alliance with France right before ww2 or the allies merely scouting the Ardennes, the entire plan would not have worked.
The maginot line was built under the premise that Belgium was a French ally so it would link with Belgian fortifications and rivers.
Because Belgium voided her alliance with France, the allied plan was forced to improvised into something similar; the allies would simply rush into Belgium once Germany invaded, and try to take up the defensive positions which they were supposed to have had. This tunnelvision of strategy caused them to neglect any defensive attention towards Sedan and the Ardennes, and it created chaos in Belgium (especially when german paratroopers managed to capture belgian fortifications at ligning speed) which contributed to the successful encirclement by the Germans.
On paper Germany was horribly outmatched by the allies. France alone began outproducing Germany in aircrafts, and Germany was already facing a resource crisis because Romania was still a French ally in 1940, and the Germans failed to secure narvik (and this the iron) even with most of Norway occupied.
French and British armament, especially tanks, were superior to Germany in both armor and firepower. The only saving grace for Germany was her doctrine and tactics, which were yet untested (only against second-rate polish military) si neither the French nor the Germans themselves were sure how they would stand against the western armies. The German generals were extremely pessimistic about Case Yellow, and it's a core reason why Hitler insisted on the high-risk-high-reward Ardennes offensive, because it was germanys only real chance of any victory.