Fantastic logic...Hmmm..had the Germans not walked into France, WWII would not have been necessary either...
if the French had just listened to the blitzkrieg needs of the germans the occupation could have been avoided altogether!
Actually Germany invaded Poland. Following the invasion the other European powers declared war, making the German invasion of France (via Belgium as always) in some respects a pre-emptive strike.
Some historians suggest that if Hitler could just have fought a war in the East he would have preferred to, but knew it was an impossibility in geopolitical terms. Naturally once he finished in the East he would have turned West anyway.