Last week, King Abdullah of Jordan became the first Arab head of state to travel to Baghdad since the 2003 war. From there, he urged his fellow leaders to re-engage with Iraq, calling it a "source of strength for the Arab nation".

What took him there, five long years after the fall of Saddam Hussein, might have been, in part, Jordan's economic needs: being on good terms with Iraq guarantees a recently agreed deal to provide Amman with discounted Iraqi oil.