BCH chain will have a small hash rate? I thought the powers of Jihan Wu and some of the other Chinese miners are riding under his banner in support of the fork?
But it will be way lower than what BTC segwit will have after the split. BTC supporters can easily attack this minor chain and like OP have speculated BCC might struggle to survive from spam attacks.
Doesn't bitcoincash have an adaptive difficulty unlike BTC? If there is a spam attack, there will be network congestion, and there will be a huge drop in difficulty, making mining there very profitable if you point your miners to the right place. Bitmain and VIA partners have quite a bit of hash power. Actually, they may have a lot more than we think, given they also have older mining equipment that wasn't profitable right now.
I think BCC can be spam-attacked, and it may be its end. Or maybe it's the beginning of a great future? If it is established it suffered large scale spam attacks and it is able to clear them reasonably well (not perfectly, just ok), I think it will give credibility to the coin.