I assume one that doesn’t involve breaking up to create a new country. Plenty of wars like that, like the English civil wars between different political faction

I assume one that doesn’t involve breaking up to create a new country. Plenty of wars like that, like the English civil wars between different political factions[0]. But I’m still going to call it the US civil war. It’s what it’s called, even if it might not the fit the traditional definition. [0]: https://en.m.wikipedia.org/wiki/English_Civil_War https://en.m.wikipedia.org/wiki/English_Civil_War