Libya faces many new challenges, but first comes a moment of joy as the despised Colonel Muammar Qaddafi loses control of his capital city, his last stronghold. Now the work of building a new Libya begins.
In Libya victory celebrations first, tough questions later
As the Libyan rebels drove, surprisingly unopposed, into Tripoli, they might have reflected that this was a long-anticipated, endlessly delayed move.
When protests began in Libya in February, the pundits predicted that the Qaddafi regime would fall swiftly. That was false and the rebels have taken a long, bloody road to the capital.
The toppling of Tripoli is an important, essential milestone, but it is not the end. Though it has been purchased with much blood, the end of the Qaddafi regime is merely the beginning of the real Libyan revolution.
In the coming days, there will be much talk about rebuilding Libya, about developing functioning institutions, about rebuilding the oil infrastructure, about life after the colonel.
And in the coming weeks and months there will be conflicts, political and maybe armed, as the country restarts itself after more than 40 years of one-man rule and ponderous talk of the Libyan revolution losing its way.
But today is not the moment for that. The rebels can allow themselves time to celebrate what they have accomplished.
Tomorrow and in the days after, there will be serious questions to address. And the most pressing of these will be security.
These are dangerous times for Tripoli and for Libya. Dangerous in a small sense, because there are lots of hyped-up, excited young men with guns on the streets of Tripoli, far from their home in the east.
Dangerous, too, because the regime has not yet surrendered. There are pockets of resistance in Tripoli, many heavily armed, and unknown snipers.
Dangerous too in a larger sense because the future is uncertain and rivalries within the TNC and within Libyan society, that were once contained by Col Qaddafi's rule, could explode into the open.
The murder of Abdel Fattah Younis, the Transitional National Council's head of armed forces who defected from the Qaddafi government, apparently by factions within the TNC, highlights the seriousness of this tension.
In an interview yesterday, Mustafa Abdel Jalil, the chairman of the TNC, alluded to these divisions.
"There are extremist Islamist groups that seek to have revenge and to create turbulence in the Libyan society. I will not be honoured to be the head of a National Transitional Council with such rebels working for it."
Then there will be political questions, the biggest of which is what will happen to Col Qaddafi - when he is found - and his remaining sons and close allies.
The situation is still in flux: as this newspaper goes to print, there is no word on what has happened to Col Qaddafi, nor to his sons Khamis and Mu'atassim. The son who appeared most likely to succeed him, Saif Al Islam, has been arrested, while another son, Mohammed, was captured after a gun-battle at his home live during a television interview.
These legal questions are likely to divide Libya, assuming the patriarch of the Qaddafi regime is not subject to a Mussolini-style execution.
A drawn-out trial like that of the Iraqi dictator Saddam Hussein could exacerbate tensions present in Libyan society, while a trial at the International Criminal Court would feel like justice imposed by outsiders.
And finally, safe passage to retirement in another country would cheat Libyans of a chance for justice.
There is also the question of the remnants of the old regime, of Qaddafi loyalists in the political and security apparatus.
But this is not the moment for those questions. It is a moment to reflect on how far Libya and the people prepared to fight for it have come.
From a small demonstration in Benghazi on February 15, protests and unrest grew and spread. There was a sense that, as Tunisians and Egyptians had toppled their leaders in a relatively short time, Libyans might do the same. But Col Qaddafi and his forces fought back and, within a month, the rebel forces were on the defensive.
What turned the tide, gradually, was the involvement of the international community, led by Nato and Arab countries, and the bravery of the Libyan rebels, mostly ordinary civilians taking up weapons for the first time. Bit by bit, they took back their country.
Yes, it has taken six months, and it may yet take much longer for this war to be called over, but a few months to liberate a regime of 42 years is short.
That's why this is also a moment to reflect on what the Arab uprisings have meant.
Watching and reporting the Arab world these days can sometimes feel like a waiting game. That these are historical days in the region is not in doubt, but the news business can sometimes attempt to compress long weeks of history into easily digestible narratives.
Hence the talk of the "stagnation" of the uprisings, though it has been barely six months since the region rose up. What the entry of the Libyan rebels into Tripoli - and the people still protesting, still fighting, in Yemen and Syria - shows is that the Arab Spring is still on course, days and weeks and months after it began.
The best course of action for the other republics is also the best course of action for the Libyan rebels: having come this far, keep calm and keep going.