Is tehre any way that, at some point between WWII & the USSR's collapse in 1991, there could've been mass race riots- along the scale of East St Louis 1917, the Red Summer 1919 or Detroit 1943- between local Muslims vs ethnic Russians & other Slavs ? OTL, there were some racial disturbances in 1986 & 1989 in Uzbekistan between Uzbeks & Meskhetian Turks in the Ferghana Valley, plus don't forget the 1916 Kazakh/Kyrgyz rising but how bout mass urban disturbances entailing ethnic rivalries breaking out in open intercommunal warfare on the streets, & the NKVD/KGB/Border Guards & Red Army needing to be called out in force ? How would the USSR have looked had word of such race riots leaked out ?