Syria was originally the chief suspect in Mr Hariri’s death, having motive and opportunity. The political history of Lebanon in the years before the assassination witnessed an increasingly poisonous atmosphere between the victim and those in power in Damascus.
So the revelation by Der Spiegel, a German magazine, in 2009 that Hezbollah may have played a role came as a shock to most Lebanese. While it may have seemed that Damascus was off the hook, sources close to the tribunal say that the working assumption of investigators continues to be that the order came from the Syrian leadership, possibly in coordination with Iran, even if Hezbollah performed the job.
The organisation simply did not have the latitude to independently carry out an assassination. Mr Hariri, after all, had global influence, boasting friendships with leaders including Jacques Chirac, the French President.
UN investigators apparently have yet to tease out the chain of evidence that can lead them from the newly-indicted ground level Hezbollah operators to those who authorised the assassination. That task may have been rendered even harder by a series of mysterious killings of key security personnel in Syria since 2005, all of whom may have had knowledge of the assassination.
They include Ghazi Kanaan, for many years Syria’s proconsul in Lebanon, who was found dead in his Damascus office in October 2005, apparently from a self-inflicted shot to the head. Imad Mughniyah was killed in Damascus by a car bomb in February 2008, and six months later General Mohammed Suleiman, a security adviser to President Assad, was shot dead at his beach chalet on the Mediterranean coast. One theory holds that the killings cut the ties between those who murdered Mr Hariri and those who gave the order. Nicholas Blanford is the author of Killing Mr Lebanon: The Assassination of Rafik Hariri and Its Impact on the Middle East (IB Tauris 2006)