Soviets(aka communists or The Reds) are part of the USSR. They are portrayed as an enemy, which means 60 seconds! and 60 parsecs! may take place during the Cold War, and the main characters are Americans.
They are mentioned in 60 seconds! and make a physical appearance in 60 parsecs as an enemy in the same fashion as space pirates and death robots . If you are powerless to drive them off, then they presumably transform the shuttle into a communist one.
Also, there's a slim chance one of your crew mates may turn out to be a communist in the traitor events in 60 parsecs!.