If you take ACW to literally mean 'American Civil War' as in 'a civil war in the US' instead of just 'the South secedes again'... there was a long-lasting meme post '68 that the US was on the brink of an inter-race war between the black ghettos and the white suburbs.... Of course this never happened but word is still out on how plausible a national uprising of civil war prpoprtions would have been. Some say, it was mostly sensationalism and fearmongering. Others say it could have happened if the right factors came together. Others say that we just got lucky. Regarddless, it did make for some interesting graphic novel plotlines back when I was growing up.