Capitalism survived what Karl Marx predicted as its imminent demise by making a market out of the proletariat. Capitalism, wherever it exists, survives to the extent that it offers something to people not themselves capitalists. Our tycoons, executives, and big landowners seem to have forgotten that fact.
Wouldn't this tie into the 'assurational' vs. penal model of social control? Of course the owning class prefer penal control of its slaves, but perhaps the other works better.
Power can be one of two things: the ability to do good for people and get appreciated for it -- or the ability to make people suffer should they fail to comply. Doing good for people and winning allies or customers requires more cleverness and self-reflection. Otherwise power comes from brutality.
The feudal lord had control over serfs that one can hardly imagine today -- he could murder at will. I don't know how prevalent the
jus primae noctis was, but if the husband resisted the rape of his new wife by the feudal lord he would die a violent death. Maybe that is the heritage of the tradition that newlyweds get away as fast as possible from the place of the marriage for its consummation.
On more banal matters -- if one failed to turn out as much agricultural production as necessary, one did not eat. If one fled a brutal master one was a literal felon as a fugitive, and one's life was be forfeit. The Church? Its hierarchy aped that of the economic order, with those from 'low' backgrounds becoming toiling monks or at most parish priests assigned to the rural area where the feudal lord was still all-powerful. Priests of aristocratic origin rapidly advanced in the Church hierarchy, and not surprisingly they maintained their political and economic loyalties. Such priests of course blessed the wheel that broke the fugitive or the kindling upon ignition that consigned the heretic or rebel to death by burning. It's hardly surprising that Christendom developed a powerful imagery of Heaven and Hell -- because Heaven was evident for the Elect of the social order and Hell was never far from the reality for the working poor.
Control by cruelty can be very effective. It's far easier to get people to work to exhaustion on starvation rations if one can threaten people with agonizing death for non-compliance (like threatening to cast anyone who doesn't produce enough shells in a concentration-camp factory into a crematorium without having first been gassed, hanged, or shot). It is far easier to get people to do suicide charges on the battlefield if there are people trained to bayonet any soldier who fails to go forward.
Control by cruelty is terribly inflexible -- and what it can produce in an order that degrades humanity into machines is rarely valuable. A command society may be good at churning out cheap commodities, but real innovation requires that there be freedom. The horrible age of terror of medieval Europe was a singularly-impoverished time, one that could have made the hunter-gatherer era look good by contrast. It well fits leaders low on a scale of moral development.