I believe its coming. It won't be in 5 years. One of the states, either a California or Florida (Texas is the obvious guess, but I think they've imported enough blue blood over the past 10 years, that they won't be the first to try to exit), will file a petition to secede. It will be labeled as unconstitutional and sent to the SC. The 3 non-Trump R justices will vote against it, as it is technically against the Constitution. The 3 Trump justices and the 3 Dem justices will likely vote whichever way is most expedient for the party. But if (when?) the SC votes it down, then civil war will break out. A civil war would devastate America as it would allow other governments to pivot away from the use of the dollar as the market currency, at which point the debt load 120% of GDP explodes as the country attempts to finance a war while seeing the drop in GDP that war would bring.
To prevent civil war, Congress could, in theory, negotiate a Brexit style exit for said state(s) thus offloading a portion of the federal debt onto that newly formed independent country, but the catagion effect would shatter the US. If California was granted secession (hypothetically), then Oregon and Washington would likely secede with them or immediately there after. If Florida negotiated a secession, you can likely bet that Alabama, South Carolina, and Mississippi would all want to be a part of that 'new country'. And suddenly the US is being carved up a few states at a time. I doubt the dollar would survive that.
Either option would lead to the end of America.
Interesting scenarios play-out. I personally don't see the non-Marxist Justices as being quite as political as you imply. Of course Jackson, Kagan, and Soto will simply vote their political ideology. Not sure that I see it as a state-by-state either. I think it will be more a single national conflict, with of course Blue, Red, and Purple states each playing out slightly differently.
I think it goes down starting in Jan/Feb 2025. As we've seen, the DNC (austensibly the Biden Administration) and Deep State are tripling down on lawfare against the US Citizenry. And of course the payouts to mentally ill fringe society residents through welfare programs, institutionalization of perversion, and massive hiring of mentally deranged into government positions.
If Biden wins a second term, ATF, DOJ, FDA, Homeland, and military will start kicking in doors of American Citizens. Next up of course is armed resistance. I don't see the ATF and FBI having wide scale local police/sheriff support, nor alignment with rank and file military to "eradicate" the 400M legally owned firearms.
Key example is the Arkansas Airport Director. Now that it's out that ATF turned off their body cams for their 6AM no knock home invasion, it's fairly well known their likely modus operandi.
On the flipside, when Trump is elected the perverts will riot. Which if they stay in sterile business districts the Citizenry will stand back and let the "authorities" manage. It's when the 10M illegals and well funded Leftists move into neighborhoods that Citizens won't tolerate- then the shooting starts.
And when that happens, I don't see the majority of police, sheriff, state police and even military raising arms against what have always been in the past law abiding citizens.
Blue states Citizenry will grin and bear it. Red won't face Authoritarian rule. Purple states are the wildcards as they have sizeable populations of both deep Red and Deep Blue. On the positive note, I personally don't know a single Marxist that's as well armed or proficient as any Conservatives.
This guy has some interesting analyses.
Here is an interesting view from 20-30 year olds.