Again, I disagree. The point is always about character - else the democracies would not have been invented in the first place. It was an endeavor to create a better system, and was called for because of the excesses of kings and lords (I will stay in the English/feudal vernacular because it is easy - I do know there were democracies before the English, and other Euro-feudal systems).
Character breeds merit, and merit breeds character. Character cannot be taught. It is learned by exposure, in trial and tribulation. The American system was merit based in it's true sense (not what we have today). That really isn't the case for monarchy. The inevitable result of a caste-based system is a privileged class. and a privileged class, born to their station, has no real means of discovering character/merit, with the possible exception of a defensive war.
There are examples aplenty of lords and kings being so corrupt or inept that they left their children penniless upon their death (or even prior to), not to mention what they did to their charge (the people). So in that, your point cannot hold.
And I might add, as an aside (and another can of worms), that the establishment of one caste will naturally and invariably create another: So one need not try to envision a case where there are only kings and nobles atop an otherwise classless, upwardly mobile society. The establishment of the goodman/freeman castes in England were an aberration in monarchical terms - And that class (free land holders, merchants) is precisely the catalyst which caused liberty to begin to grow in the modern age - The middle-class was born in them. It can be inferred from this that a part of what the noble class must do is to keep the people down, and in subjection, as a measure of their own preservation. The middle class is the death of nobility - ergo, there can be no middle class... which means there will only be the lower class.
[...] Nothing remotely similar can be said of an elected politician.[...]
At this point, I would again draw a firm distinction between a politician and a statesman. Your conversation doesn't seem to do so, lumping all under the less savory term of politician. The statesman has the same sense of duty/honor/country as any fine noble you could mention, and is not a mere "salesman selling government". By the same token, statesmen are almost as rare as fine nobles are.
Virtually every vice found in our system can be found in a monarchical system: The Noble Court served the very same service as the American Lobby. There was every bit as much vice, bribery, greed, and corruption; the same sort of business deals, and old-boy networks, glad-handing, and favoritism. These are all symptomatic of any sort of power. And that brings me back to my original premise, that there is no recourse in the Monarchy: Power corrupts. Absolute power corrupts, absolutely.
I agree that nobility should be earned as well as heritable, and in most feudal societies it was. Also, removal of nobility status was a common punishment for civic lapses.
But still one must start in nobles - and further winnow the field to find an almost non-existent noble who has earned merit. Do you see how specious the argument is? What of the merchant who won his fortune fair and square, by good business practices and proper accounting? No matter how much wisdom he has gained, and merit he has earned; no matter how much more valuable his merit is than any lord; he can be of no value to governance (w/o the House of Commons) without nobility being conferred.
Here, a man can arrive a pauper, and by his own merit, attain wealth and go on to be of service (if elected). And many, many have done so. All of those people would not have any chance of being of real service in a monarchy. In fact, the chances are that he would remain a pauper, unable to break out of the caste he was born into, as that is the inevitable and historical state of monarchy.
Just by the statistical fact, more results come from a wider pool, and that is why democracies are so prosperous, inventive, intuitive, and quick. They allow the cream to rise to the top. Monarchy assumes the cream is already there.
Character cannot be taught. It is learned by exposure, in trial and tribulation.
So is it taught by trial and tribulation at least? You seem to say two contradictory things. The reality is that a kid from a noble family is taught that his future is in national service: he will have the obligation larger than his own family. He observes his father doing his work; his dad will take him to military campaigns and teach him to fight, -- he will learn the military craft, to endure pain, to face fear. A courtier would learn manners, sophistication, arts, basic science, diplomatic and bureaucratic skills. Of course it can be learned. It can also be learned without the family, and so is the case with gained nobility; but the family helps. We actually have that in America as well: we have generations that go to West Point, or into politics.
Nobility can also be lost. Cowardice, disloyalty are not crimes, but they are faults of character and the aristicratic system punishes them.
the establishment of one caste will naturally and invariably create another
That must be why the feudal system did not have castes.
I would again draw a firm distinction between a politician and a statesman.
Yes. There is no question that John Adams, Lincoln, Reagan were statesmen. But our system breeds them not. The early American system, buoyed on Protestant spirituality did so more than ours. Today, even if we have a president dedicated to serve the nation and blessed with the long vision, -- what made Reagan great was his vision of the victory in the Cold War, -- the system discourages that. Notably, Reagan's other agenda, reducing the scope of the government, failed.