"First: The French had a treaty obligation to the Russians. They would not have stayed home."

The French had treaty obligations with Poland in 1939, but really didn't follow through with them. Ever hear of the sitskrieg? It lasted from Sep 3, 1939 to May 10, 1940 when Germany, not France, made the first move.

"Second: The Germans went through Belgium to avoid heavy fortifications along the France-Germany border. The French would have had no trouble getting past their own fortifications to invade Germany."

The French may have in fact been able to get past their own border fortifications (maybe), but trying to get through German border fortifications would have been a different story all together.

"Third: The French had an ax to grind with the Germans. Take a look at the outcome of the Franco-Prussian War (1870-1871). The war reparations placed on France were intended to cripple that country economically for two generations, thus giving Germany a chance to replace France as the dominant Continental power. Instead, the French rallied as a nation and paid it off in a decade. The sting of that humiliation was still there. "

The French army wasn't capable of carrying out major offensive actions, it was a defensive army. Had the Germans stayed put and dug in on the border the French would not have been able to do anything. Any attempts to attack would have resulted in massive casualities on their part.

"Fourth: France had a long-standing special relationship with Poland. To see that nation swallowed by Germany without putting up a fight would have been unthinkable."

Poland didn't exist as a nation in 1914 (see map below), but was a part of the Russian Empire. It didn't gain it's independece until 1919, when it was created out of part of the territory Germany had gained after defeating Russia in 1917.

"Fifth: Do you have any memory at all of what happened to Napoleon's army when he invaded Russia? Hint: the same thing happened to Hitler."

Germany did defeat Russia in 1917 (as I stated above), and they did it while fighting a war on three fronts against France, Britain, Russia, and Italy. Had the war not spread to include Britain and Italy, they would have defeated them a couple of years earlier. As a result of their victory over Russia, they did take all of the territory from my previous post. After the war, Poland, the Baltic States, Finland, Byelorussia, and the Ukraine were formed out of this territory.

"Read the books. You'll understand better."

I've got every one of those books, plus a few dozen more on WWI. The subject is a passion of mine.