To adress your second point: The point isn't in justification. The difference I'm pointing at is the attitude and mental model of the world of the Commander, i.e. the parent. And this causes some crucial differences in behavior that aren't accounted for by the lack of need to justify oneself or even the consideration of not being a peer.
Sure, we could say some (or perhaps even most, YMMV) workplace managers behave a certain way that is similar to those parents and children. We could say the same for militaries. I care little for what one could say about the similarities or the words that can or "should" be used.
Key point: Children are often treated by their parents in a manner completely dissimilar to every other case of family member or person with whom they live.
Key point 2: This behavior of parents towards children has sufficient differences from typical cases of social-class or not-peer behaviors for me to not label it as a standard case of such. I believe it would be very misleading. Parents often carefully control the "private life" of their children; what they eat, what they do at any given time, who they interact with, what they say, and even what they think to some extent.
Even in military settings, moreso in workplaces, these examples are not at all carefully monitored and controlled with punishments and threats of various kinds, and even those that are generally end the moment your shift ends and you walk out the door, with some exceptions regarding PR and such (e.g. politicians and people with similar occupations).
Key Point 3: Behaviors, social norms and laws differ between all those cases, and I would argue that laws and social norms, at least, are more similar between pets and children than they are between children and employees/nonofficers. If an employee doesn't behave as a manager wishes, they are limited in their options, and the interactions and roles are socially clear. A manager cannot threaten to confiscate an employee's phone for not properly cleaning up after themselves in the bathroom, nor are they legally and socially allowed to dole out corporal punishment for an employee that talks back to them or asks the wrong questions.
Yes, this is a touchy issue for me, so I apologize if I come across as less polite than I think.
LessWrong has been having fun lately with posts about sexism, racism, and academic openness. And here just like everywhere else, somebody inevitably claims taboo status for any number of entirely obvious truths, e.g. "top level mathematicians and physicists are almost invariably male," "black people have lower IQ scores than white people," and "black people are statistically more criminal than whites." In my experience, these are not actually taboo, and I think my experience is generalizable. I'll illustrate.
You're at a bar and you meet a fellow named Bill. Bill's a nice guy, but somehow the conversation strayed Hitler-game style to World War II. Bill thinks the war was avoidable. Bill thinks the Holocaust would not have happened were it not for the war, and that some of the Holocaust was a reaction to actual Jewish subterfuge and abuse. Bill thinks that the Holocaust was not an essential, early plan of the Nazis, because it only happened after the war began. Bill thinks that the number of casualties has been overestimated. Bill claims that Allied abuses, e.g. the bombing of Dresden, have been glossed over and ignored, while fantastic lies about Jews being systematically turned into soap have propagated. Bill thinks that the Holocaust has become a sort of national religion, abused by self-interested Jews and defenders of Zionist foreign policy, and that the freedom of those who doubt it is under serious attack. Bill starts listing other things he's not allowed to say. Bill doesn't think that the end of slavery was all that good for "the blacks," and that the negatives of busing and forced integration have often outweighed the positives. Bill has personally been the victim of black-on-white crimes and racism. Bill is a hereditarian. Bill doesn't think that dropping an n-bomb should ruin a public career.
Here's the problem: everything Bill has said is either true, a matter of serious debate, or otherwise a matter of high likelihood and reasonableness. Yet you feel nervous. Perhaps you're upset. That's the power of taboo, right? Society is punishing truth-telling! First they came for the realists... Rationalists, to arms!
Or.
We can recognize that statements like these correlate with certain false beliefs and nasty sentiments of the sort that actually are taboo. It's just like when somebody says, "well science doesn't know everything." To this, I think, "duh, and you're probably a creationist or medical quack or something similarly credible." Or when somebody says, "the government lies to us." To this, I think, "obviously, and you're likely a Truther or something." Bill is probably an anti-Semite, but Bill doesn't just say, "I'm an anti-Semite," because that really is taboo. He might even believe that he shouldn't be considered something awful like an anti-Semite. Bill probably doesn't think Bill so unpleasant.
That's the paradox: "taboo" statements like black crime statistics are to some extent "taboo" for sound, rationalist reasons. But "taboo" is not taboo: it's about context. People who think that such statements are taboo are probably bad at communicating, and people often think they're racists and misogynists because they probably are on good rationalist grounds. If you want to talk about statistical representatives on the topic of race, be ready to understand that those who are listening will have background knowledge about the other views you might hold.
All this is the leadup to my question: what highly probable or effectively certain truths are genuinely taboo? I'm trying to avoid answers like "there are fewer women in mathematics" or "the size of my penis," since these are context sensitive, but not really taboo within a reasonable range of circumstances. I'm also not particularly interested in value commitments or ideologies. Yes, employers will punish labor organizers and radical political views can get you filtered. But these aren't clear matters of fact. I also don't mean sensitive topics like abortion or religion, nor do I mean "taboo within a political party."
Is there really anything true that we simply cannot say? I have the US in mind especially, but I'm interested in other countries as well. I'm sure there are things that deserve the label, but I've found that the most frequently given examples don't hold water. I think hereditarianism is a close contender, but it's not an "obvious truth." Rather, my understanding is that it is a serious position. It's also only contextually taboo. If it were a definitive finding, it could perhaps become taboo, though I think it more likely that it would be somewhat reluctantly accepted.
Any suggestions? If we find some really serious examples, we might figure out a way to talk about them.