David Cameron called parliament back from vacation thinking that they would quickly approve a resolution giving him effectively a blank check to attack Syria. He argued that it was clear to him that the Syrian government had used chemical weapons and that the UN investigation was unnecessary, which is also the Obama administration position. When that ran into headwinds and he seemed likely to lose, he agreed to a watered down resolution that would revisit the issue later depending on what the UN inspectors reported.
But even members of his own party still deserted him and he lost 285-273, effectively killing any chance that the UK would join the US in any campaign in Syria in the near future. The Guardian has a live blog of today’s events. It seems like 30 Conservatives and 11 Liberal Democrats joined the opposition Labour party. The fact that about 30 Labour MPs were absent means that the margin defeat could have been even greater.
Not only is this a huge defeat for Cameron, inciting calls for his resignation, it also puts president Obama in a bad position. If even his most loyal client state is not able to go along with him, it makes him look increasingly isolated.