A civil war? Nah. The population is neither well-armed or politically strong enough to develop any opposition. In a way it reminds me of those brainless blobs that reelected BN after receiving measly handouts. The non-muslims are more likely to pusssy out than play Sharia house with the Sultan.

Of course, I'm not ruling out the prospect of an uprising, but Brunei is still pretty livable. It's going to take a lot of economic decline for something like that to ever happen, provided there is enough willing locals left to pull it off.