Excellent article, Ed!
Do you know what the difference is between Bernie Sanders and Hillary Clinton? Bernie admits he's a socialist.
You said, "Fundamentally, the current political battles reflect conflicting visions: government as protector of our individual liberty, leaving us free to live our lives as we will; or government as the benevolent parent that helps us helpless people directly."
It's true that you and I see that as the battle, but those who understand and want liberty are a small minority. The vast majority see it as either the strong authoritarian father figure (currently Trump but that can change in a minute) who will mete out the overdue punishments and protect us by attacking the enemies, versus the soft motherly progressive who will help everyone and make all conflicts go away (althought, that has a tendency to morph into an angry grievance-warrior).
One problem with a culture that comes at politics in this child-like fashion, where they feel an attraction that is based upon some sort of parental projection, is that if they are nervous they may play it safe by choosing the parent-figure that is less extreme and is the more establishment figure (e.g., Bush as the GOP safe pick, and Hillary as the Dem who is corrupt and untrustworthy but more establishment - or Biden if Hillary gets too toxic).
It is going to take a lot of educating to get a significant number of voters who understand that government MUST be strictly limited to protecting individual rights and that everything else is much better handled by a marketplace that will provide anything that people demand.
This requires a level of emotional maturity in politics such that people get over this idea of using government as the authority figure that will force others to do what 'they should.' It starts by accepting that people will do lots of things disgusting or frightening - even offensive to the viewer, but as long as no one is violating anyone's rights it is, none the less, an infinitely better environment. And the passing of time will see that a free marketplace crafts for each group of people a corner of the culture that reflects their likes and suits them best.