Content, reasonably comfortable populations don't try to kill their leaders, their townhall speakers, their representatives.
It looks like this is part of a wider societal breakdown that the Western world (Western Europe, USA, and to some extent Canada and Australia) are experiencing. The systems that have been constructed worked for a while, and worked fairly well.
No longer.
Politics is now a dead end - no matter who you vote for, some corporation owns your politics and, by extension, you. The leaders want to spend even more on weapons to fight wars, and even less on social security nets to keep their own poorer citizens fed. Poorer citizens who's ranks swell year and year because certain people hoard masses of wealth and refuse to countenance any concept of the greater good; they worked a million times harder in their comfortable office than any man who spends 40 hours a week breaking his back digging holes in the road in rain, wind, or shine. So why shouldn't they be able to keep everything and watch the rest of the world go to hell?
60 years ago, one income could let you support a family and even allow you to buy a home. Now, two people both earning can barely get enough to scrape buy and owning your home is a pipe dream.
People want answers. And in such times populists carry the day. Trump is one, Kirk was another. People who's message is simple: It is the "other" who is your problem. The "other" being an immigrant, some ethnic minority group, feminists, environmentalists, or some other group.
But the thing about populists is that the blade they wield has two edges. It doesn't just radicalize the people who believe their messages, it radicalizes the people who don't. For them, the "other" becomes the opposite demographic. Indigenous locals, white people, males, or whatever.
Wedges are being driven between demographics which really need to live together and exist alongside each other. The problems both sides face are not truly caused by the other, but the culture wars breaking out between them are a useful distraction for those who's fault it really all is, and who are in a position to fix things, so they use the media, they use social media, and ham it all up.
Not surprising that people will see "the enemy" and decide to reach for a weapon...