Frakking RA3 had to have the Soviets going back in time to kill Einstein off. Einstein was a totally awesome part of the RA games. The Allies wouldn't have the awesome Chronosphere, Prism Tanks, or any other of his excellent inventions. Killing Einstein also introduced a paradox because if the Soviets went back in time to kill Einstein, how could Einstein go back in time to kill Hitler, causing the events of RA1? And if RA1 didn't happen because Einstein wasn't around to kill Hitler, then how could the Soviets create time travel to go back in time and kill an Einstein who never existed?
EDIT: Okay, let me clarify the whole RA3 paradox. Einstein went back in time and killed Hitler, so there was no Nazi Germany and the Soviet Union and Allies went to war. If the Soviets went back in time to kill Einstein, then Einstein never went back in time to kill Hitler, meaning Hitler was around to create Nazi Germany, meaning WWII should have happened as planned, so it is impossible for the events of the RA series to take place because Hitler was never killed by a time-traveling Einstein.