While the Government tried to argue that the failed assassination attempt on Tim Torlot was a mark of al-Qaeda’s frustration at repeated attacks on its mountain hideouts, it also demonstrated that the militants are capital of striking in the capital, despite increased training of Yemeni troops by US forces.

Despite its constant pledges to tackle al-Qaeda, the Government has been distracted by what it sees as more pressing concerns. An uneasy truce with Shia rebels in the north, aimed at ending the six-year-old conflict that displaced more than a quarter of a million people, has been plagued by accusations from both sides that the other is not honouring the agreement. In the south discontent is still simmering, with the once-independent region resentful that the Government benefits from its oil and other natural resources while investing so little in its infrastructure.

Yemen sits on the crossroads between the world’s important oil routes and the Shia rebellion in the north, which dragged in Saudi troops last year, has sparked a tensions between Sunni Riyadh and Shia Tehran, the two leading global leaders in oil production.

But Yemen also sits at a key nexus for al-Qaeda, many of whose most hardcore fighters have been recruited in the rugged, dirt-poor country that is the ancestral homeland of Osama bin Laden. Just south of Saudi Arabia, with Islam's holiest sites, and just north of the lawless Horn of Africa, into which al-Qaeda has begun to move in recent years, Yemen could become a safe haven for the terrorists, many of whom hail from its fiercely independent tribes.

Yemen’s unrest is further stoked by its dwindling oil supplies and booming young population growing up in deep poverty, as well as the fear that it could be the first country in the world to run out of fresh water.

The West is also hindered in its military involvement in the country after senior clerics threatened to declare a jihad, or holy war, if foreign troops were deployed there. A similar deployment in Saudi Arabia after the first Gulf War in 1991 helped boost to al-Qaeda’s recruitment and funding.