It used to be the custom, in Catholic kingdoms, for the king to wash the feet of twelve poor men at the Mass of Our Lord’s Supper on Holy Thursday. Alas, the practice has now almost entirely disappeared, even in countries that still have a nominal king. The one quasi-exception, ironically enough, is England, where the Queen still distributes money and hosts a dinner on this night.
The idea, of course, was that the king ruled as a participation in the Kingship of Christ; a kind of subordinate under-monarchy to the Davidic line, and traditionally the Last Supper was held as the event where Christ united the old and new monarchies. And like his Divine Master, the king was called to be a servant to his people as well as a leader (that is, in fact, what authority means in part; responsibility).
Today we don’t think in those terms anymore. We think in terms of social contracts and unalienable rights and consent of the governed and so forth; that the rulers are in charge because they’re the ones we the people have hired to safeguard our rights. More of a work-for-hire situation than a covenant or personal relationship.
Obviously, if these are our ‘employees’ then we’re getting cheated, but never mind that now.
It wouldn’t really make sense, thematically, for the President to be washing his people’s feet. Theoretically, they’re not ‘his people’, but his fellow citizens who have hired him to do a job. Or at the very least it would imply a different kind of relationship than what we’re told we have.
(And of course, if any of the criminals currently squatting in the White House were to wash someone’s feet, I would recommend they get them re-washed as quickly as possible).
In our world, every man is a king, and mutual economic benefit replaces loyalty. Everyone is free and equal, and therefore we have contracts and jobs to be done, not service and devotion. Our service is rendered to communities, to ‘our fellow man’, or the country as a whole more than to those above or below us, since there is (theoretically) no one below anyone else and no one above us except the country itself. But it’s rather difficult to wash a country’s feet.
In any case, the King of Kings didn’t seem to find it degrading to play the role of a servant. Something to consider.