Not really a "civil war"-- basically, bitcoin will keep working, even without the segwit upgrade if it gets delayed another year or two, and there might be some new altcoins that could be spun off from the current bitcoin, and there might be some brand confusion for a while as people wonder whether something incompatible with the bitcoin network is still bitcoin.

Here is some background:

http://www.coindesk.com/bitcoins-segwit2x-scaling-proposal-c...

https://medium.com/@jimmysong/segwit2x-what-you-need-to-know...

https://bitcoinmagazine.com/articles/major-exchanges-will-co...

https://bitcoinmagazine.com/articles/countdown-segwit-these-...

https://news.ycombinator.com/item?id=14758587

https://www.reddit.com/r/sound8bits/comments/5xre70/the_orig...

https://www.reddit.com/r/Bitcoin/comments/6mz19j/potential_n...

https://www.reddit.com/r/Bitcoin/comments/6mgecw/frankensegw...

https://bitcoinmagazine.com/articles/bitcoin-unlimited-miner... or https://medium.com/@WhalePanda/verified-chatlogs-why-jihan-a...

how about some peer review yo, https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2017... and https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2017...