I did not want to get bogged down in details but from your reply you force me to. Thanks to
lobosrul for giving
Swiss some more details about what I meant
France could have easily stopped the reoccupation of the Rhineland by advancing to the border or maybe 50 miles into German territory. The French Army was capable of this. At this point in time, the German General staff would have overthrown Hitler and this would have taken care of the Hitler problem.
Please notice when the British Expeditionary Force landed in France.
Please research your history of Austria and the relatively new nation of Germany. Better yet, tell an Austrian that he is actually German and see the reaction. There are German speaking areas of Switzerland also...aren't there

Also Mussolini was against this and stopped the Germans from doing this sooner than '38.
Please research the steps taken to breakup Czechoslovakia and how at any point the Allies could have mobilized and stopped this from happening.
I have read all the new information about Stalin invading the Reich but I am not too sure if I believe it. It could have been a feint to keep Hitler in check?! Or Soviet propaganda to explain their terrible showing in 1941 and save Stalin's face!
After the invasion of Poland the Allies did not take any serious ground action against Germany. The Western border was open to an attack by the French Army. Even a WW1 type Army using WW1 tactics!
We cut off the Japanese oil supply because of the invasion of China. Maybe a bit naive but this is how Americans think and still think today. We found ourselves in many situations like this in our history.
You really need to get your facts straight about the size of the combined Allied Armies in 1939 and the size of Germany's. In 1939 Germany was not in a war footing either...this only started in 1943-44. I personally think that the French would have done a lot better in offense than they did in defence!