Western betrayal
Western betrayal is the view and perception that the Western Allies (specifically the United Kingdom, France, and the United States) failed to meet their legal, diplomatic, military, and moral obligations to the Czechoslovaks and Poles before, during, and after World War II. It also sometimes refers to the treatment of other Central and Eastern European states by those three nations. The concept primarily derives from several events, including British and French appeasement towards Nazi Germany during its 1938 occupation of Czechoslovakia and the perceived failure of Britain and France to adequately assist the Poles during the German invasion of Poland in 1939.