Why do you abbreviate USSR that way? The first I assumed was a typo, the second makes it look intentional.

I do not see how that tracks from either the English translation, the original Russian name for the country: "Сою́з Сове́тских Социалисти́ческих Респу́блик", or the transliteration: "Soyúz Sovétskikh Sotsialistícheskikh Respúblik".