I was taking issue with your use of the term "self-evident" as it applies to the Golden Rule. Yet it is clearly not self-evident when approached from your rationalist point of view. "Self-evident" implies that it needs no proof; the ready availability of excellent counter-examples demonstrates the need for proof. Hence, it is not and cannot be self-evident to the rationalist.
A truly rational person would note that the king has a better chance of not being harmed than does the man who counts on his fellow man to obey the golden rule. You yourself don't do that -- IIRC you're a big gun rights supporter. Why? Because you don't trust your fellow man to invariably follow the golden rule, and are instead relying on a show of force to avoid being harmed.
If you were rational, you'd conclude from this that the king is right: force is the only way. You'd also have to conclude that the golden rule was for chumps, as it requires a tremendous degree of trust that is not necessarily warranted. Instead, you've given the golden rule a tremendous weight that cannot be justified on rational grounds.
So we're back to our original and long-standing argument, which you're still avoiding.