I am quite convinced Popper would have disagreed that the line doesn't needs to be drawn (in some cases) before violence — at least this is what I learned about him when I studied philosophy in Vienna, the city where he grew up in.
Popper e.g. also says that the goal of elections is to have a transfer of power without having to have civil wars, guillotines and other violent means. This means to prevent violence we have to maintain certain rules.
This doesn't mean however, that we have to wait till bad actors in fact act violently, after e.g. having stated they want to abolish these rules, after threatening violence, after breaking present rules and stretching present conventions etc. This means that he didn't want to suppress intolerant views (IF they can be hold in balance with rational arguments and public discourse) — instead he would plead to limit their effects on society (thus reducing potential future violence).
But it has been over a decade since I read Popper, so maybe you read something I didn't.
Popper e.g. also says that the goal of elections is to have a transfer of power without having to have civil wars, guillotines and other violent means. This means to prevent violence we have to maintain certain rules.
This doesn't mean however, that we have to wait till bad actors in fact act violently, after e.g. having stated they want to abolish these rules, after threatening violence, after breaking present rules and stretching present conventions etc. This means that he didn't want to suppress intolerant views (IF they can be hold in balance with rational arguments and public discourse) — instead he would plead to limit their effects on society (thus reducing potential future violence).
But it has been over a decade since I read Popper, so maybe you read something I didn't.