Lets say every red states eventually backs this. The Supremes either decide to not hear the case, or worse, hear it and rule in favor of the defense. Is it war then?

I couldn't say. It would mean the SCOTUS has endorsed manifest fraud in MI, WI, GA, and PA, and conservatives in red states will know that they will never be allowed to have a hand in choosing the president ever again (because even if we win, they'll just dump phony ballots into the count until we lose).

What do you do with that? I know it's not a sustainable political situation long term.