I wish I was better aware of history and other cultures, because I lack context for this observation…
…but it seems to me that there has been a change over the last 30ish years with how these events are portrayed. Roughly, we’ve gone from “nutjob(s) doing nutjob stuff” to “this is proof that my (mainstream) political opponents are evil”.
The obvious example is the Gabby Giffords shooting. Was that the moment when the inflection became complete?
I think back to OKC. An obvious right wing, militia, “furious over Waco and Ruby Ridge” thing, but my sense at the time was that there was very little demand that Republican pols denounce it. At least not uniquely. It was understood that McVeigh had no supporters in respectable circles.
The media did take a shot at pinning that on Rush Limbaugh, but even that feels like it fell flat.
Anyway, it feels like the evolution from “nutjob doing nutjob stuff” to “something we can exploit for political advantage” is a meaningful cultural moment.
But like I said in the beginning, maybe I’m just not aware enough of how things are/were over time and distance.