Heinlein's observation rests on something subtler than the notion that guns make people fearful of each other—he's describing how mutual vulnerability creates accountability. When everyone understands they cannot impose their will through force without consequences, the calculus of civility changes: you must persuade rather than coerce, negotiate rather than dominate. The insight applies equally to digital spaces, where anonymity removes consequences and politeness evaporates, or to workplaces where power imbalances are steep and unchecked—in both cases, the absence of reciprocal risk produces incivility. What makes this worth considering is that it points not to guns themselves, but to the deeper human truth that manners flourish when no one can safely dismiss another person's capacity to affect them.