Five years ago, a former Prime Minister of Lebanon and longtime American ally, named Rafiq Hariri, was assassinated by a car bomb in the heart of Beirut. The incident fueled a popular uprising of Lebanese civilians commonly referred to as the “Cedar Revolution,” which would quickly pressure Syrian forces out of Lebanon after decades of occupation.

Yet the removal of Syrian troops from Lebanese territory was not the only aftershock of the Hariri killing. The United States government under President George W. Bush would later blame Syrian authorities for orchestrating the attack on a moderate and Western Arab politician. Washington would sever all diplomatic ties with the Syrians until five years later, when President Barack Obama entered the Oval Office. The Shiite militant movement Hezbollah, which was already on the American security radar for past terrorist attacks, would bear the brunt of America’s attention.

Now in August 2010, after that intense and tumultuous time in Lebanese politics, a UN investigation will release its final judgment on the Hariri murder. Syria has been exonerated from any wrongdoing. That leaves Hezbollah operatives as the main instigators of the attack.

On the eve of the judgment, with everyone preparing to finger Hezbollah for the crime, Lebanon is once again bracing for a political firestorm that could quickly turn violent. The irony is that Rafiq Hariri’s son, Saad Hariri, is now the man who has to keep the lid on the simmering pot.

Unfortunately, this is going to be exceedingly difficult for the younger Hariri to accomplish. He is in a tough position regardless of who is blamed for his father’s murder.

Prime Minister Hariri can either put his firm weight and political support behind the commission’s ruling, making his position known to the world but hurt his appeal with the majority of the Lebanese population (who happen to be Shia and highly supportive of Hezbollah as a social organization). Or he could endorse Hezbollah’s position and denounce the results. He may also choose to order the creation of a new independent commission aiming to uncovering evidence that may have been previously overlooked by the original investigation. This move, however, would hurt him with the United States and Israel at a time when Lebanon is already experiencing a harsh rebuke over the Israeli border incident.

So what can Hariri do?

So far, he’s been trying to straddle both sides by largely keeping his mouth shut and letting the tribunal do its job. This is what Hariri is probably going to do until a verdict is reached.

If Hezbollah isn’t fingered, Hariri has dodged a bullet. But if Hezbollah is in fact implicated, then Hariri may choose to call another investigation in order to keep a potentially violent situation from getting out of control. The Lebanese government’s main concern is to limit a potential civil war between Sunnis and Shiites. The best way to do that is to divert pressure to an outside actor.

This is all speculation of course. In either event, Hariri Junior is going to strain some relationships.