The first conspiracy against Hitler predates July 20th 1944, and even the outbreak Second World War. Additionally, it was the conspiracy with the greatest objective chances of success. It was officially headed by the Chief of the German General Staff, Franz Halder, and supported by many senior army generals. However, the actual leader was Generaloberst Ludwig Beck-a member of the General Staff who thought that Hitler’s aggressive methods of oppression were morally and politically wrong.
The conspiracy was incredibly well organized; it included orders down to divisional level for the seizure of key installations and effective disarming of the Nazi paramilitary organizations; it was meant to be triggered by orders to invade Czechoslovakia (which was owned by France and Britain-victors of WW1). The logical behind this was that the German people only adored Hitler because he had reversed the much of the humiliation faced by Germany in the First World War without war.
Germans were terrified of a new world war, and if they saw that Hitler was risking the new and improved Germany for the sake of annexing another country, they would stop supporting him. However, France and Britain actually complied with Hitler’s demands and signed away the territorial integrity of Czechoslovakia.
They accepted Hitler’s word that it was his “last” territorial goal, because they too were afraid of a new world war and wanted to make an alliance with him against Communism. Thus, the most promising conspiracy to stop Nazism, the Holocaust, and the Second World War in its tracks was tossed aside...and the rest is history.