What you can do though, is destroy the foundation of democracy by being tolerant towards discrimination, for the sake of not "banning ideas"
--> "Why not turn people who are not able to work anymore into a nutricious paste for others? It was just a question! You can't silence me, this is a democracy!!"
You can’t ban ideas, because they will hide behind other ideas, until you ban everything. If the AfD is banned and voters start holding blank pieces of paper and posting *** like in Russia, everyone knows what they mean, but will you start arresting people holding blank pieces of paper and posting *** like in Russia?
But in this case, just listening to them is enough. They're openly calling for violations of our constitution. How much longer do we have to wait before we may take their threats seriously?
The first step, arresting the most obvious, won’t lead to a Reign of Terror on its own. But I don’t think it will be effective either.