But I suppose I'll engage despite it being hard to take your confusion about America seriously. In places such as the Lubyanka basement, Butovo firing range, and other NKVD sites, prisoners were often shot in the back of the head while standing or seated. Some facilities had drainage systems or chutes. Bodies were trucked to pre-prepared mass graves (Katyn, Kurapaty, Bykivnia, and many others). This was part of a deliberate system of class-based and political terror: the Red Terror under Lenin, the Great Purge, dekulakization, the Holodomor, and the gulag system.
If you can show me where in history America implemented this system, such that you could honestly be confused whether I was talking about Russia or America, I would be truly impressed.