1939, September 1. The III-rd Reich invades Poland.
1939, September 3. France and Britain declares war against Germany.
1940, April 8, Germany invades Norway.
1940, May 10, Germany invades Belgium.
1940, June 14, German soldiers occupy Paris.

The British Army in France 1939 Army and French Air Force personnel outside a dugout named ’10 Downing Street’ on the edge of an airfield, 28 November 1939.

OK. War makes no sense. Starting one, that is.
Unless you have to defend yourself, of course!

It was Hitler’s Germany which had started WWII.
France and Britain declaring war on Germany was nothing but a formality.
But what happened next…

Waiting for 8 months while your opponent was busy elsewhere makes even less sense. Than starting the war in the first place…

Counterfactual history is interesting.
Imagining ‘what could have happened if’, we may learn how people think.

We know what happened.
We’re not happy with much of it. It would have been a lot better if WWII was never fought. In the first place. For all of us.
The next best thing would have been a lot shorter war. France and Britain invading Germany while Hitler and Stalin were dividing Poland among themselves.

I’m not going to enumerate arguments. Neither for nor against. I don’t actually know whether the war would have been shorter or not. Whether the end would have been significantly different. Or in which way different…
But I would really like to understand what was going on in Chamberlain’s head! As well as in Daladier’s. The British and French prime-ministers at that time, respectively.

On the other hand…
1936. Hitler had ordered his army to enter the Rhineland region. In breach of the Versailles Treaty.
1938. Hitler had occupied Austria.
1939, March. Hitler invaded what was left of Czechoslovakia, breaching what he had promised in September 1938.
During this time, France and Britain did nothing!

Not so drole anymore, eh…