Dr Julian Lewis: Although historical analogies are dangerous, I fear that if we were in 1917 now, the Government would be advocating backing the Russian revolution on the basis that the Mensheviks might come out on top and not the Bolsheviks. Is it not a fact that thousands of al-Qaeda fighters are fighting in order to overthrow Assad? If they get their hands on his chemical weapons stocks, woe betide us in the west.

[The Secretary of State for Foreign and Commonwealth Affairs (Mr William Hague): My hon. Friend is quite right about the importance of extremist groups not getting their hands on chemical weapons stocks. That is one reason for strengthening more moderate groups in Syria, rather than letting the extremists gain greater strength, which is what is happening on the current trajectory. I will not follow him into all his historical analogies, but he will be well aware that Winston Churchill pretty much pursued the policy he was just talking about.]