By Kevin Connolly
BBC News, Beirut
Beirut connects the Middle Eastern and Mediterranean parts of the Arab world
Sometimes it can be hard to judge when things are moving and when they are not.
Stand with your back to the city of Beirut and stare out into the dull-blue waters of the eastern Mediterranean and some trick of the light makes it appear that the great container ships on the horizon are utterly still. They are not, of course.
Turn away for a moment to marvel at the way Beirut sits untidily on a narrow slip of land between the mountains and the sea like old jewellery piled on to a shelf. When you turn back, the ship will have moved on, and will appear to be still again.
Some sorts of change, of course, are easier to see and measure than others.
There are soldiers at the end of the driveway of my modest tourist hotel, for example, who are noticeably more relaxed at the end of this week of political upheaval in Lebanon, than they were at the start.
They are not guarding the hotel itself but a military installation tucked away behind it. An incongruous piece of what passes for town planning here.
Nothing could stand out more glaringly against our white-painted walls than the tangle of camouflage webbing which is meant to make their sentry box invisible.
A little way down the elegant curve of the Corniche stands a Phoenician lighthouse, one of the few remaining traces of the great trading civilisation of the ancient world which slowly dwindled in importance in the last few centuries before the birth of Christ.
The Phoenicians in some ways are rather unlucky to be remembered as the forgotten civilisation of the ancient world.
Their explorers once managed to circumnavigate Africa - one of history's great feats of navigation - but because their account of the rising and setting of the sun as seen from the southern hemisphere seemed so implausible, no-one believed them.
Part of their wealth was based on exporting a purple dye to Greece where it was used for dying the robes of a fashion-conscious elite, but eventually the snails from whose crushed shells the dye was made became extinct.
You wonder if they foresaw all the changes that would flow from that one, apparently minor change.
It has been that way, too, in Lebanese politics this week.
Mr Mikati says he is dedicated to the unity of Lebanon
On the face of it, the country's complex political machinery creaked into action and delivered a new prime minister to replace Saad Hariri whose government collapsed in acrimony a few weeks back.
The rules, of course, have to be complex to reflect the patchwork of ethnic and religious groups which are bound together here by a rather fragile set of working agreements.
The president has to be a Maronite Christian, the prime minister a Sunni Muslim and the speaker of the national parliament a member of the Shia community.
So, the small visible change involved the replacement of one Sunni Prime Minister, Saad Hariri, with another, Najib Mikati.
The larger change it betokened was the steady rise in power of Hezbollah, the heavily armed and socially active Shia movement whose power as a state within a state has long thrown a shadow across conventional politics in Lebanon. It backs the personally moderate Mr Mikati.
America regards Hezbollah as a terrorist organisation plain and simple, and Hezbollah almost certainly outguns the army of the Lebanese state itself.
It has the powerful backing of Iran and, because it is strongest down towards the edgy southern frontier, where Lebanon meets the state of Israel, many Israelis now feel they effectively share a border with their implacable Iranian enemies.
It is a remarkable outcome to a political crisis which was triggered when Hezbollah walked out of the previous government because an international tribunal was apparently about to accuse some of its senior members of involvement in the 2005 murder of Rafik Hariri, prime minister at the time.
He was, of course, the father of Saad, the loser in this latest power struggle.
For a day there was a sense of tension here.
There have been riots in Cairo and other Egyptian cities in recent days
There were protests in the areas where support for the Hariri family is strongest, but then the anger abated, at least for now.
Perhaps that is because even as the jigsaw pieces of the Lebanese constitution were being cautiously assembled into a new pattern, all eyes in the Arab world, which had been on Tunis, began to turn to Cairo.
I sat in a cafe where through curling wisps of sweet smoke from gurgling shisha pipes, affluent Lebanese watched the satellite pictures from Egypt.
It is of course another sign of change, but for the moment no-one really knows how much lasting change will flow from it.
In the Arab world, with its huge and growing population of young people, it feels like an exciting prospect. To the democratic governments of the West, which have allowed themselves to feel very comfortable with essentially non-democratic governments in places like Egypt, it must feel like a complex and unwelcome challenge.
The darker aspect of those regimes is always overlooked, on the grounds that they at least promise a kind of stability. Now they do not necessarily promise even that and the unpredictable voices calling for democracy on the street can hardly be ignored.
It is always hard to measure change and movement and to understand it, even when it is happening right in front of your eyes, as those of us watching the shipping lanes out on the eastern Mediterranean could tell you.
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