I doubt it'll be an organised purge like we would all hope (be it a political purge or a criminal purge with huge amounts going to prison forever)

My prediction is more that all the safety nets that have kept the left safe will simply collapse and they'll die in huge numbers. The New York incident is one of those examples, they are going to walk around, doing their thing like they always do, not realising NO ONE is protecting them anymore and they'll simply die. By the time they realise the change it'll be too late and so many will have died they'll no longer be a voice in society. The right that have guns won't rush to their aid, they'll focus on protecting their own first and it'll be a bloodbath for years to come.