France did have a large army with superior tanks overall. The deficiency was in leadership, organization and morale. The generals were hedging their bets on the Maginot line. Tanks were organized as they were in WWI serving primarily as infantry support. Furthermore, a key element credited to the Germans success was that of the FM radios in each tank whereas the French communicated via flags. Morale, it did not seem that the French wanted to fight at all.

So the size of the army does not matter.

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