To quote Posner
"An extremely important, even a defining, element of the judicial protocol is what Aristotle called corrective justice. That means judging the case rather than the parties, 2 1 an aspiration given symbolic expression in statues of justice as a blindfolded goddess and in the judicial oath requiring judges to make decisions without respect to persons. It is also the essential meaning of the "rule of law." It means abstracting from the particular characteristics of the litigants - their personal attractiveness, their standing in the community, their wealth or poverty, their political affiliation, their race, sex, ethnicity, and so forth - and seeing them rather as representatives of abstract positions or interests: the careless victim, the reckless driver, the copier of copyrighted work, and so forth. " --[
Posner 2006]
A domain specific notion of the "rule of law", to be sure. But inside the courtroom, it matters a great deal. Outside the courtroom, it's a more abstract notion, that the government both exercises its powers by writing laws of general applicability rather than by attainting specific persons and is, perhaps more importantly, formally bound by laws itself.
You argued that
There are states which do not consider themselves bound by either "the rule of law" or even the notion of "rule by law". A person, in such a state who advocates against the ruling authorities (or
against the very concept of hierarchical authorities) might very find themselves the target of
State violence,
One could more accurately argue
or even
It's not enough that the government uses
formal legal rituals to exercise its powers. It's that in some sense that government is constrained by the laws, and not merely political expediency. To kill a man, the government must prove (beyond a reasonable doubt) that the man has violated some law (defining a particular capital crime) that was conceived before the alleged crime took place. Even if the government is convinced of the man's dangerous nature, it cannot act outside the framework of laws, and it wold probably expose itself to legal liability were it to act outside the law.
Th
e notion that certain individuals constitute a criminal class ("illegals") without legal rights, and should be locked up forthwith is a particular affront to the rule of law.