Question

Would the soviet union had attacked germany in world war 2

Answer 1

First of all. Soviet Union did start World War II - together with Germany. World War II started with German invasion of Poland in September 1939, only a week after the Molotov–Ribbentrop Pact was signed between SU and Nazi Germany. With that SU gave a green light to German invasion and Germany promised half a Poland, Baltics, Finland and Bessarabia to SU in return. It is highly improbable that Hitler would have dared to invade Poland without that agreement as he would have risked 2-front war. After that event SU and Germany acted as close allies until June 1941, i.e. nearly 2 years.