Okay, let's look at that.
The British wrote the Polish Colonels a blank check. (Poland was essentially a military dictatorship at that point) even though they knew they were in no position to attack Germany and provide relief.
Instead, they insisted on war; Hitler cut a deal with Stalin to divvy up Poland and also give Russia the Baltic states, Moldova, and a free hand in Finland. This drove Finland and Romania into the German camp. Also, Hungary and what was left of Slovakia at that point. So now, instead of worrying about an expanded war in the east, Hitler had a free hand to deal with the west.
Now, imagine if you would, if with better diplomacy, the UK cut the deal with Stalin, arranged an alliance in the eastern countries to resist further German aggression. Maybe work with Mussolini, who wasn't wed to Hitler at that point. (Mussolini actually had contempt for Hitler.)
But no, because the Munich Conference was a black eye for Chamberlain, his mouth was writing checks his ass couldn't cash. Lucky for him, he didn't see the mess that followed.