It is kinda a red flag (not the good kind) but at the same time we also need to accept that none of us will live to see the perfection of the communist ideal. We all have reactionary brain worms that have thus far gone unexamined and if some people are hooked on the idea of revenge for the suffering they have endured I don’t really begrudge them. These people should not be put in charge of anything but they do have their use. Righteous anger and violence will be needed to guard against counter revolution.