The demographic-political breakdown of Lebanon is usually understood as Shiites against Christians and Sunni. However, it is easy to forget the (Sunni) Palestinian minority. Many Palestinians are not integrated into the Sunni mainstream and are not likely to support a pro-Western government.
This is being demonstrated by the heavy fighting in Tripoli that has left over seventy people dead. The events started with a bank robbery. After police raided the suspects' home, al Qaeda-aligned Fatah al-Islam responded by attacking a nearby army post. With that a full scale battle erupted. The Lebanese army is surprising everyone with their strong efforts and willingness to fight in an urban combat setting.
The fighting is already producing results. One of the terrorists killed was wanted in Germany for a failed bomb attack. The group is well connected with al Qaeda and other terrorist groups.
The War on Terrorism is a war on networks. Fatah al-Islam is a node in the al Qaeda network.