>>149834553 (OP)
>Why doesn't Batman just
He can't do anything that permanently gets rid of the Joker or prevents the Joker from being the Joker and doing Joker things in any way. ANY. WAY. Doesn't matter if it's lethal or not, anything that removes the Joker from the formula is a no-go. If you want to stop seeing the Joker being the Joker and doing Joker things, then the only sane option you have is to stop consuming any Batman-related media. Now please stop fucking asking questions along the lines of "why don't they just prevent the entire plot from happening before it even begins", because you already know the fucking answer, and I'm sick and tired of seeing people constantly ask the same question that they already know the answer to.