By Roger Hardy
BBC Middle East analyst
The Lebanese demonstrators on the streets of Beirut are in jubilant mood.
It is not just that the world is, for once, paying attention to events in their tiny country.
Some protesters have left the streets, but many remain
They feel Syria is finally succumbing to international pressure to end its 30-year military presence.
Many opposition politicians, however, are in rather more sober mood.
They realise that the fall of the government this week - dramatic though it was - is only one step towards the achievement of their aims.
They want Syria out of Lebanon, lock, stock and barrel.
And that means its intelligence agents as well as its 15,000 troops.
But first they want the formation of a neutral caretaker government which will do three things - all of them sensitive:
- Find out who killed former Prime Minister Rafik Hariri on 14 February
- Pave the way for free parliamentary elections in May
- Negotiate a timetable for a full Syrian withdrawal.
Traditionally, a new prime minister is chosen as a result of consultations between the president and MPs.
The current President, Emile Lahoud, is deeply unpopular because of his close ties to Syria.
So the opposition must first decide whether it is ready to co-operate with him at all.
The anti-Syrian alliance brings together many, but not all, of Lebanon's main communities.
Always in the forefront of opposition to Syrian dominance have been the Maronite Christians.
But the killing of Mr Hariri has led others to support the Christian-led opposition.
Both the Druze - a heterodox Muslim sect - and the Sunni Muslims have now joined hands in calling for the Syrians to go.
Military intervention begins in 1976
30,000 troops in Lebanon during 1980s, currently 15,000
Syrian forces crucial in ending the Lebanese civil war in 1990 and maintaining peace
Calls for departure of the Syrians increase gradually with Israeli withdrawal in 2000
UN resolution calling for withdrawal of all foreign forces passed in Sept 2004
But the biggest community, the Shia, are standing aloof.
This is not because they like the Syrian occupation, but because their main political party and militia, Hezbollah, is Syrian-backed.
The current crisis has put Hezbollah in an awkward position.
Its role in forcing Israel out of southern Lebanon has won it a good deal of popular support in Lebanon.
It accordingly has an interest in showing itself to be a patriotic party that puts Lebanon's concerns first.
But at the same time it is unhappy at the efforts of the United States and Israel to weaken its two external patrons, Syria and Iran.
Whatever weakens their geo-political position weakens Hezbollah too.
How Hezbollah resolves this dilemma will be an important factor in determining the outcome of the current crisis.