Until 1938 britain and france basically ignored hitlers foreign policy do you think this was wise what amde them change thier minds

France and Britain didn't want another war. They did everything they could to stop it, when they should've declared war when Germany first started their aggression. It would've made the war a lot shorter. 

However, it was when Germany declared war on Poland when they realized that Germany could not be appeased, and could not be contained. So there was war. 

We need to see the poster