And that, on a practical level, the remains of the coercive state will take action on assassins and groups associated with assassins in a way that is brutal, destructive, and disproportionate. So even if you win, you lose.

>is the reason for assassination's inefficacy the martyrdom
>effect, or that it removes a figurehead but leaves the
>political vehicle, in his opinion?

The state is a relationship, in his view. That means untangling it is much tougher, and though the idea of propaganda of the deed (which basically says assassination is justified because the apparatus of the state infuses our lives with constant coercive violence) makes the issue about more than a single death for him, Landauer still believes that disentangling needs to be done interiorly: a cultural change where we view our relationships to each other in a radically transformed way.