Regarding Stalin’s example and the responsibility of the Russian people for his actions

Hello Rabbi,
In the last lesson on judging evil, you mentioned the example of Stalin and the responsibility of the Russian people for his actions. You mentioned the issue of collective responsibility. On the other hand, I remember you saying in the past that not every group of people constitutes a collective. For a group of people to constitute a collective, there must be something that binds them together (such as a system of law and justice). And so, regarding Stalin’s example, there is no collective of the Russian people upon whom collective responsibility can be imposed. Isn’t that so?
Another question that occurred to me in this context is, how does this example parallel Aharon Barak’s story of the unreasonable action of the reasonable person?
Best regards,