I’ve been arguing and discussing with several groups, and had an insight.
The Tea Party is today’s echo of the SDS. Both are/were mostly well-meaning, passionate, law-abiding (and only passively violating the law) people who were relying on lies and disinformation. The liars and disinformers were part of nastier subgroups, which in the SDS case included such groups as the Weather Underground and Black Panthers. We’re seeing some of this in the Three Percenters and OathKeepers, but I suspect (not know, just suspect) that the specific echo of the WU is still in the party itself.