Start pardoning every supporter of the ruling party, and see your country turn INTO Russia.
That is the most basic misunderstanding of autocratic regimes.
You are not safe because you're member or supporter of the ruling party.
a) there is no "ruling party", there's the maximo lider and his henchmen
b) the henchmen can never outgrow the maximo lider - as soon as they get too large, they'll go
c) the henchmen have to be culled every now and then in order to ensure discipline
There's literally thousands of examples troughout history, from "decimation" in the roman legions to "failed" generals in WW2 to "disgraced" oligarchs to the assasination of Kim's own brother.