Stalin wanted the Germans to be exhausted in the war with the British and the French, and then as soon as the three sides of the conflict were weakened by the war with each other, Stalin would be able to send several million Red Army soldiers to Europe. It was a secret Soviet operation codenamed "Thunderstorm" to conquer Europe and establish communism there. Therefore, at the time of Barbarossa, Stalin concentrated tens of thousands of tanks, thousands of planes and millions of soldiers on the border of Germany and the USSR, he was waiting for Germany to weaken in order to strike at her at the moment when Germany, France, Britain would run out of steam from the war with each other. At the beginning of the Second World War, many believed that it would be militarily similar to the First World War, where the front line was moving slowly and the main part of the war was focused on trench warfare. Therefore, Stalin was waiting for him to strike at a weakened Europe.