The Hezballah center of gravity
There is more. I think the attacks in Beirut are to disorient the Hezzies command and control and their logistic train including the destruction of their finance network. It is part of isolating the battlefield. Wretchard is correct on the destruction of Hezballah fighters in southern Iraq. Hezballah will lose a war of attrition on that front if the Israelis continue to press. If they take care of the fighters the rockets and other equipment will be destroyed in the process.
The first question that must be answered in divining IDF intentions in Lebanon is what the center of gravity of the Hezbollah is, because that is what the IDF must be aiming to destroy. The two obvious ones are Hezbollah's ability to influence the Lebanese government and the motor of that influence -- the military force that Hezbollah maintains in the south. A step down we can ask, what is the most important component of Hezbollah's power in the south? Again the answer is easy. It is the Hezbollah cadres themselves. Hezbollah's most precious possession isn't Katyushas, long-range rockets, night vision goggles or antitank missiles or electronic equipment. It is the trained core of its military force. Equipment can be replaced but Hezbollah's cadres represent an expensive, almost irreplaceable investment. In them resides the organizational knowledge of Nasrallah's organization. It embodies man-decades of operational experience against Israel. Rockets can be replaced. The stars of Hezbollah's operational force are less expendable.
From this observation I'm going to say that despite the received wisdom of the newspapers to the contrary, the fighting at Maroun al-Ras and Bint Jbeil have been and continue to be an unmitigated defeat for the Hezbollah. The Hezbollah are doing the single most stupid thing imaginable for a guerilla organization. They are fighting to keep territory. Oh, I know that this will be justified in terms of "inflicting casualties" on the Israelis. But the Hez are probably losing 10 for every Israeli lost. A bad bargain for Israel you say? No. A bad bargain for Hezbollah to trade their terrorist elite for highly trained but nevertheless conventional infantry. Guerillas should trade 1 for 10, not 10 for 1.
Reduced to its essentials, the IDF strategy may be ridiculously simple: fix the Hezbollah force in Southern Lebanon while detaching its command structure from the field by simultaneously striking Beirut. One of the great mysteries, upon which newpaper accounts shed no light, is why the IDF should so furiously pulverize Hezbollah's enclaves in southern Beirut, blockade the port and disable the airport. The object isn't to shut down Lebanon. It is to momentarily disorient the Hezbollah headquarters in Beirut, so that in a moment of absentmindedness, the Hezbollah forces in Southern Lebanon will do what comes most naturally: commit themselves against the IDF.