Related Clues:
- Stalin's state
- U.S. ally in WWII
- 1984 Olympics boycotter
- Cold war superpower
- 20th-c. nation
- World power until 1991
- Beatles' "Back in the ---"
- Former GDR ally
- Five-Year Plan empire
- WWII ally
- Stalingrad's land, for short
- Home to every undisputed world chess champions during the 1950's and 1960's
- ''Back in the ___''
- START I treaty party
- 31 Across subject