Why did the partition of Czechoslovakia teach "European democracies"nothing? Did they want to conclude a military Alliance with the USSR and stop Hitler's aggression? And if not, why not? On a broad documentary basis, leading Russian and foreign historians present a picture of world politics in 1939. They provide an answer to the main question: why was not an anti-Hitler coalition formed in 1939 and a system of collective security created that could have made it possible to avoid an escalation of the situation. For the first time, photos of the original Soviet-German Treaty and its Secret Protocol provided by the foreign Ministry are included in the Appendix to the collection.The book is intended for politicians, experts, journalists and a wide range of readers interested in the history of Europe and the Second world war.