The New York Times' piece on the British parliament's rejection of a forceful response in Syria contains a strange passage:
The vote took Britain into new constitutional territory, the lawmaker added, with Parliament effectively vetoing military action. Political recriminations are likely. But there was little disguising the humiliation for Mr. Cameron, who recalled Parliament specifically for a motion that he first watered down, then lost.
There is also a deep wariness here of using military force without the explicit backing of international law, expressed most clearly in a Security Council resolution, though without one, Britain participated fully in the NATO campaign to unseat Col. Muammar el-Qaddafi in Libya.
There was of course a Security Council resolution authorizing force in Libya (Resolution 1973). The Times is either a) unaware of this; or b) suggesting provocatively that the Council resolution was stretched beyond its meaning by NATO. That latter claim is plausible but it certainly deserves more explanation than the article provides.