The terrace of Irish House at the United Nations Interim Force in Lebanon was a good vantage point from which to watch the escalation of the three-week-old war yesterday. To our left, in the waters just off the Israeli-Lebanese frontier two Hetz (arrow in Hebrew) class warships fired volley after volley of artillery shells.
A few seconds after each loud crack of an outgoing shell, we saw a flash of fire on the beachhead at Ras al-Bayada, and smoke from impacts further inland, just to the east of Tyre. There was the usual thunder of Israeli jets, and the occasional whoosh of a Hizbullah multiple rocket launcher.
The naval bombardment, which continued sporadically throughout the day, was only one element in a conflict which expanded dramatically yesterday.
Overnight, Israel launched a raid on the Bekaa valley town of Baalbek, capturing five Hizbullah men and killing 10 others, according to the Israelis.
Lebanese television reported that the captured men were from the Nasrallah and Musawi families - common names among Shia Muslims, but possibly relatives of the movement's leaders.
The Israelis attacked the hospital built by the Ayatollah Khomeini Foundation, and a Lebanese army post, killing a soldier and wounding two others.
Hizbullah retaliated with the heaviest barrage of rockets and missiles into Israel since the war started on July 12th - about 200 according to most estimates.
One of the missiles reached 70 kilometres into Israel, also a record. The launch of the missile into central Israel seemed a response to Israeli prime minister Ehud Olmert's assertion that Israel had "entirely destroyed" Hizbullah infrastructure.
"If it continues like this, Beirut will be bombed again," says Ryszard Morczynski, the political affairs officer for Unifil. The Lebanese capital had not been bombed for the previous six days.
Israel expanded its ground offensive, engaging in street fighting with rifles and heavy machine guns in villages like Ayta ash Shaab. Other ground incursions with tanks and troops occurred on the outskirts of Yarun, Hula, Addaisseh and Kfar Kila.
"They cross the Blue Line (the closest thing Lebanon has to a border with Israel) go to the outskirts of a village, bombard it with everything from bullets to heavy artillery and helicopter gunships," says a security source. "They make sure that everything is dead in the village - even a cat."
Israeli ground troops who crossed the Blue Line near Markabé yesterday shelled into Taibé, At-Tiri, Shaqra and Bra-Sheet, all villages in the former Irish/Italian area.
Israel warned villagers further west, in the Tayr Harsa , Shihin and Yarin area, to fly white flags from their houses if they were not involved in the conflict, a sign that a ground incursion may be imminent there too.
Yesterday evening I heard the crack of two outgoing Hizbullah rockets from a hillside north of Tyre, followed by incoming Israeli shells and the sound of jets and drones. It was a sign that Hizbullah is being pushed north but is still fighting back.
According to Unifil sources, that is true in one sense: "All Hizbullah positions and tunnels are finished already," says Mr Morczynski. A security source estimated the number of former Hizbullah positions along the Blue Line at 30, ranging from makeshift tents to watchtowers. Mr Olmert yesterday spoke of 700.
Conversation centres on these questions. Do the Israelis merely intend to create a demilitarised no man's land two or three kilometres deep along the Blue Line, or do they intend to go all the way to the Litani river, 20 kilometres into Lebanon?
Is a ceasefire really within reach this week, or will the conflict drag on until the Jewish holidays of Yom Kippur and Rosh Hoshana, as one Unifil source predicted.
"It's like the Irish weather; it changes by the hour," says Lt Col John Molloy, senior liaison officer at Unifil between the Lebanese and Israeli armies and commander of the 10-man Irish contingent in Unifil and Observer Group Lebanon.
Mr Morczynski believes a two- or three-kilometre "security zone" is the more likely Israeli option. It would prevent Hizbullah kidnapping or killing their soldiers," he explains. "You don't need ground troops, you watch and anything that moves you shoot at."
Another source speculated that Israel will use UAVs (unmanned aerial vehicles) or drones capable of launching weapons to enforce this new zone until an as yet ill-defined international force arrives.
There will be a strong temptation, Mr Morczysnki says, to flatten the villages in the zone. "Its what the Russians did in Chechnya," he adds. "They call it zachistaka. It means cleaning out the population and destroying key installations so rebels do not move in as troops withdraw."
An Israeli advance all the way to the Litani would eliminate 80 per cent of Hizbullah's capacity to launch rockets at Israel, Morczysnki says. But it could be costly in terms of Israeli lives. Israel lost 790 soldiers in Lebanon in 20 years and may not have the stomach for casualties on such a scale.
The composition and mandate of the future "stabilisation force" is another source of speculation. Everyone agrees that it must be under Chapter 7 of the UN Charter ("Peace Enforcement" rather than Chapter 6 "Peace-keeping", as Unifil is). Turkey, a Muslim nation on good terms with the countries involved, appears to be the first choice to lead the force. The great unknown is the willingness of Hizbullah to co-operate.
Whatever happens, Morczynski says, "it should not be a predominantly European force nor predominantly Western, recalling the deployment of US marines and French and Italian troops in the 1983 multinational force - which ended in suicide bombings against the Americans and French.
He adds: "You can paste and copy what was being said 20 years ago. If they follow the same rationale, the same catastrophe will happen."
Most sources here concur that Hizbullah has the upper hand. "In 1967, Israel defeated three Arab countries in six days," says a security source. "After three weeks, Hizbullah are still on the ground and they are still fighting; they've won."