An observation from Complex Systems Science:
Regardless of those (internal or external) who might be seeking to generate more friction and to extract political or ideological value from it, the contemporary extremity of partisan adversarialism and dissonant turbulence that characterises the US political system has the characteristics of a dissipative system – that is, a self-propagating pattern of information and energy, like a (spiral) cyclone or hexagonal-shaped cells of water in a pot. These systems are optimally-oriented to the reproduction of their own essential and sustainable continuity – outside volition, choice or directed human agency.
A key to understanding these kinds of systems is not merely or only the artefacts, entities, sub-systems and vectors of influence within them. These complex adaptive systems generate and cultivate the environment (here, adversarial) that maximises the probability of system self-propagation through a transmission (communication) medium. The political system is a single, unified totality that self-propagates optimally through a threshold level of dissonance and partisanship. There is much more to the explanation but no time or space to unpack it and that, in abbreviation, is the zeitgeist.