He also gets into the question of the origins of Fatah al Islam, including the arguments for links to Syria, al Qaeda, and the Iraq conflict. Having done that, he turns to the question of whether or not the Future movement or the Lebanese state had provided support to Fatah al Islam:

No evidence has been presented to prove Hariri entanglement in the origins of the Nahr al-Barid fighting. Unfortunately, the theory is not entirely baseless, either. It draws upon growing fears among “moderate” Sunni regimes like Saudi Arabia, Jordan and Egypt of a resurgent “Shiite crescent” in the Arab east, the Hariri family’s close business and personal ties to the Saudi royal family and the evident community of interests among these regimes and the Siniora government in its ongoing struggle with Hizballah...

The Future Movement’s relationship with Sunni Islamism goes back further than the summer war. Since the civil war, Lebanese Sunnis have been regarded as a sect without a militia. Rafiq al-Hariri cultivated this image, distancing Future from organizations like al-Jama‘a al-Islamiyya -- which, if thuggish, is ideologically closer to the Muslim Brotherhood than the salafis. The realities of Lebanese society, and the clientelist electoral politics that reflects it, made it impossible to ignore these groups, however, and their marginal constituency.

At the start of Lebanon’s 2005 parliamentary elections, Future and al-Jama‘a al-Islamiyya declared there would be no electoral alliance between them. Since the first two rounds were virtually uncontested wins for Future and Hizballah, respectively, this was a simple matter. When, a week later, Michel Aoun emerged a victor in the third round and threatened to repeat his performance in the fourth (northern Lebanon), though, Future swung into action. Saad al-Hariri spent lavishly to support the Future list in the north, and, by all accounts, the poor Sunni villagers there turned out in droves. A portion of this largesse certainly went to al-Jama‘a al-Islamiyya. Some of it likely ended up with more extreme Islamist groups.

Hariri’s ticket took all of northern Lebanon’s 28 seats and his allies won the majority of seats in Parliament. The new legislature’s first order of business was to keep certain political promises to Hariri’s partners in the “Syria out!” demonstrations following the assassination of his father. The most prominent of these promises was the release of Lebanese Forces leader Samir Geagea, serving a life sentence for the murder of then-prime minister Rashid Karami, among others. The parliamentary pardon of Geagea on July 18, 2005 overshadowed another amnesty to a group of Sunni Muslim militants charged with being involved in Islamist cells connected to subversive activities.

In their number were 26 men tried for involvement in the Diniyya insurgency of 1999-2000, which saw more than 40 people killed, including 11 Lebanese soldiers.

...

More recently, a couple of months before the present crisis developed, salafis associated with Sidon’s Jund al-Sham group were in conflict with their neighbors in a quarter adjacent to ‘Ayn al-Hilwa. Sidon deputy Bahiyya al-Hariri (Saad’s aunt) defused the problem by paying Jund al-Sham members some thousands of dollars to leave the neighborhood. Various Palestinian sources agree several of these militants decamped to join [Fatah al Islam leader] ‘Absi in Nahr al-Barid.

...

Whether or not the Hariris and their Saudi supporters have a soft spot for salafis is not the point. Rather, it is the culture of cooptation that has marked the Lebanese government’s approach to the challenges confronting the country since the Syrian withdrawal. Rafiq al-Hariri deployed his financial resources to great effect during his political career, but his purchase of loyalties was embedded in the Syrian occupation’s security regime. With the Syrians gone, and with Sunnis set against their Shi‘i countrymen -- and with them the specter of Hizballah, the militants who stopped the Israeli army, Lebanese find the line between purchased loyalties and militant outsourcing a fuzzy one.

The whole article is worth reading, as I've left out most of his discussion of the Palestineans and their situation. It's an astonishingly clear and complete piece.