Andy McSmith's Sketch: David Cameron knows more about what is NOT going to happen in Syria than what will happen

When Tony Blair sent British troops into Iraq, he knew what they were there to do – he just could not give a clear reason why. David Cameron had the opposite problem today. He was crystal clear about “why”, but very vague about “what”.

Insofar as he answered that question at all, it was as a sequence of negatives. “Let me stress to people, this is not about getting involved in a Middle Eastern war or changing our stance in Syria, or going further into that conflict,” he stressed. The list of things the UK is not going to do lengthened during a separate interview by the Deputy Prime Minister Nick Clegg. Regime change, “open ended military intervention” and “boots on the ground” are all also off the menu.

What remained was Mr Cameron’s stern-faced insistence that the Syrian government and anyone else who might use chemical weapons had to be stopped after last week’s attack.

History is not the Prime Minister’s strongest suit. After hearing him say that “almost 100 years ago the whole world came together and said the use of chemical weapons was morally indefensible and completely wrong,” you might suppose that no one but the Syrians had used chemical weapons since the end of the 1914-18.

Actually, Saddam Hussein’s government deployed chemical weapons with horrible results in the 1980s, first against Iran, and later against the Kurds, but in those days he was on better terms with the West than either Syria or Iran, so his atrocities were overlooked.

This time, it appears, something will be done, something that Mr Cameron has promised will be “proportionate” and “legal”, but he did not elaborate on what he means by “legal” in this context.