This story just isn't going away. The killing in Syria has only intensified since I made our podcast about it. But it's become clear that despite much hand-wringing, there is little scope for united action around the world.

I've been mulling this over in an analysis article, which started off with a rather prosaic section relating the problem to a more straightforward dilemma: "Imagine you and a friend are walking along the street and see, on the other side of the road, three figures ahead of you. Two of them are bulky, bullying types, engaged in a completely one-sided fight against the third, weaker figure. Your first instinct might be to run over with your mate and rescue the victim of their brutality. But those two stocky men don't look easily beatable. What do you do?"

MPs continue to be deeply concerned – and are upping their calls for action. Former Cabinet minister Sir Malcolm Rifkind, who served as John Major's foreign secretary, has written an article for us suggesting that Britain press for a full economic embargo against Syria. He makes some pretty powerful arguments – but will this become a reality?