If you asked a State Department employee what their worst-case scenario for the Middle East was five years ago, the response might have described what is currently unfolding across the region. State power is on the ebb, sectarian conflict is widespread, and where the prospect of just one power vacuum-turned-terrorist sanctuary would have been anathema to the hawkish US administrations of yesteryear, now there are many.

One such vacuum is Yemen, though few are aware of it because the local government’s struggle has faded into obscurity against the more high-profile disasters of Syria and Iraq.