I'm probably more centerist than your average punk. I am definitely liberal, but not hard left. That's beside the point when it comes to violence.
On violence - you can post whatever "fuck the government/system/police" memes you want, but you can't post 'hehe got my local MP a little surprise for Christmas 🥰😘 picture of pipe bomb" style content here. You cannot call for people to hurt other people, even if you're 'joking'.
Personally, I don't see violence as a means to an end. I don't see it as acceptable because it just perpetuates itself, and once it starts the lines of morality get very blurry very fast. If anything, it just entrenches the opposing side and strengthens their resolve.