Division is with us since forever, but societies in the developed world are aging and thus lack the necessary "cannon fodder" of enough fit young men for a civil war. Civil wars are very often associated with youth bulges [0] and our days of having a youth bulge are over in the West.

(There is a possibility of massive influx of young men from Africa and Asia into Europe, which would replenish the potential, but that does not concern the USA.)

[0] https://blogs.worldbank.org/developmenttalk/youth-bulge-a-de...

40-y.o. somethings are less militarily capable and, these days, usually fat. They will stick to their keyboards.

But yeah, all that hate worries me as well.