This is an artifact of first past the post electoral systems, which reward polarization. You can't demonize the other parties if there's more than one to choose from and your governments are coalitions that may require you to genuinely work together next time.

Here's a former PA lawmaker, nearly elected to US congress, who may have been part of the group that breached the capitol:

https://twitter.com/Redistrict/status/1346938310359396354

I find it hard to believe that that would even work in most EU countries.