Why did the militia movement decline after 1996?

[Okay, maybe Mike Johnson is a competent parliamentarian.]

This sounds fascinating. Are there any examples of how 50s music survived in the Plains well into the 80s and 90s?

There's unfortunately not a lot of academic sources that track the development and popularity of music by region, especially not from that time and in that region, but the heartland rock that gave the Midwest its voice from the 1970s onwards (and still does according to my insider source in rural Iowa; poor guy) directly evolved out of '50s rock and roll and the folk music revival that began in the '40s. In fact, lot of future heartland rock acts started out regionally as regular rock n' roll and R&B musicians. Holdouts from the western-influenced third generation of country music, like Willie Nelson and Marty Robbins, remained popular in the Plains. The Plains were in a stasis where the contributions of hippies and non-whites throughout the 1960s mostly passed them by, and I interpret their eventual taking to metal music to be a continuation of the trends that people like Elvis symbolized in the '50s (versus the more cosmopolitan route that created disco, synthpop, hip hop, rap, and so on).

I can't remember exactly how the line goes, but there's a moment in Field of Dreams where the main character's wife, who's a coastal transplant to rural Iowa, accuses a right-wing school board member of having skipped straight from the 50s to the 70s.

[Okay, maybe Mike Johnson is a competent parliamentarian.]

1996 as the peak year is interesting to me, since that is the same year Clinton was reelected. I'm not old enough to have any special insight, but I wonder whether him reelection took the wind out of the sails of many right wingers? I could be wrong, but I feel like the right-wing backlash was less of a driving force in Obama's second term than it was in his first. Maybe the same dynamic was at play in the 90s?

While not explicitly directed at him, the Malhuer takeover and Gamergate were major in bringing about the Alt Right and the various militia movements.

You could argue that second-term opposition to Obama was more similar to the 90s militia activity than first-term opposition to him, since stuff like the Tea Party was heavily astroturfed and openly focused on resolidifying Reaganism as the American status quo, whereas Malheur and Gamergate were, whatever else can be said against them, genuinely grassroots and focused on issues other than the ones that Republican leadership wanted to talk about. You could even, somewhat more edgily, argue that the Trump opposition's adoption of "resistance" terminology was a tone-deaf attempt to brand a Tea Party-style elite-driven opposition as if it were a Malheur/Gamergate-style "netroots" opposition.