Try 2027 for a waypoint.
Not "huge militias". Dozens of heavily armed gangs squabbling over territory in major urban zones and some rural areas too.. The local Governments will be trying to play off the gangs against each other in order to maintain a semblance of control. Access to cash, manpower, and weapons will be decisive factors.
"Votes" can be manufactured as needed. Courts will rule in favor of who ever appears to be in charge.
See Chicago and Los Angles for worked examples today. Repeat in two dozen other cities and multiply the intensity by a factor of 20 or so.
Central authority will break down under economic stresses triggered by the pending insolvency of State and Municipal pension plans and Medicaid plans. This will increase exponentially by 2024 and the response will be Federal Government bailouts. The checks will be deposited every month; you may be quite certain. This of course will cause massive inflation. By 2027, things should really be cooking.
The Federal Government will be busy purging dissident individuals from civil service and any role in public life. Large corporations will be aggressively doing the same in the so-called private sectors. Think of "public-private partnerships" and what they really entail.
Large Government and large Corporations are symbiotic allies.
Governments will sponsor "Public Safety Auxiliary Forces" when they can no longer fund regular police departments. These will be local militia, and mostly with a Leftist and ethnic political orientation. They will be poorly-trained, but ultimately permitted and well-supplied with small arms.
Again, see the "Sharia Patrols" which operate in New York City with approval (or at least toleration) from the Police.
Lots of raw kindling available to start a fire when formerly middle-class people find themselves taxed out of their homes and impoverished by constantly rising prices.
Most of the kinetic activity will be localized. Others with more experience have said; "The greatest threats to your life and liberty are within five miles of where you live". That sounds right to me.
Very astute.