The fighting in Syria will go on and may spread. There is no reason whatsoever to think that missile strikes and bombing raids by outside countries will do anything but ensure that the fighting continues longer and that it spreads even wider.

And there is no reason to think that Parliament's decision will in any way prevent that happening. This wasn't about that, it was about whether Britain is seen as a great power, or rather, whether it can pretend to be a great power.

The key players in all this are the US and Russia. The prority for Russia in this is to ensure that Siyria does not become a jihadist state. Towards that end they are willing to accept the Syrian government doing whatever it thinks necessary. Using chemical weapons does not in any way advance that end, in fact it very seriously damages it. This means the Russians have every reason to prevent this happening. In this they have a common interest with the US (and Britain)'. The rational thing is to try to use this to end the civil war.