Rabbi Uri Sherki (the name is French, so excuse my spelling) often remarks that he is asked why rabbis comment on politics, and he answers, “What, then, should rabbis deal with?”
Of course, the questioners are here being polite. Instead of using the term “מתעסקים”, they might use the ruder “מתערבים”, since it’s more of an accusation than a display of respectful curiosity.
In explanation, Rabbi Sherki notes that any system that has laws for polities must have a political program. And Judaism has laws for the whole polity. In other words, the laws are aiming at some new order, in the instrumental sense.
(I don’t care to credit the accursed source the rabbi brings for this insight.)
This is all very important and correct.
(“Law as a Means to an End: Threat to the Rule of Law” by Brian Z. Tamanaha may be worth a look.)
Yet I think the question cannot be dismissed, either. The “question” is based on the sobering realization the political field itself is impossible to navigate with justice.
Here the layman’s intuition is correct (although he may feel that what is forbidden to the rabbis is permissible to himself).