To understand the symbolism of Libyan rebels running triumphantly through Muammar Gaddafi's Bab al-Aziziyahh compound yesterday, it's worth recalling what a totem of anti-Nato, anti-insurrection defiance it had been over the past six months, let alone over the previous decades.

Back in March, taken by regime minders to see the hundreds of Libyans who had gathered as "human shields" in the heavily fortified six square kilometre complex, we watched them sing, swaying, to a catchy African rhythm, words borrowed from the dictator's chilling 22 February speech. The one in which he promised to hunt down his enemies "Zenga zenga" – alleyway by alleyway; inch by inch; street by street, house by house. Then, of course, the banners – some helpfully written in English for the benefit of the TV networks – proclaimed: "Libya is united and out of your reach", and: "We are waiting for you and so are the fishes". The men, women and children had streamed past the armed soldiers, a tank and militiamen in civilian clothes armed with AK-47s to proclaim their loyalty, and shout: "Allah, Muammar, Libya wa bas" – God, Gaddafi, Libya, it's all you need.

Now, instead of being hunted down, the "rats" as Gaddafi called them, were at the compound last night; instead of the fanatical young supporters who had chanted and sang about their loyalty to the Brother Leader, it was now his opponents who clambered on top of the Libyan regime's most iconic pieces of agitprop sculpture, the huge golden fist crushing an enemy war plane, commemorating Gaddafi's survival in the face of the 1986 air strikes of Tripoli ordered by Ronald Reagan after the deadly bombing of a Berlin night club used by US servicemen. It is far from certain that all those who swore to "protect" the Libyan dictator were there voluntarily. Exiled dissidents would later say they recognised from the television pictures some of their own comrades among the crowds, men brought out of jail and forced to swell the pro-Gaddafi ranks. It will be some time before we know whether any of these were able to exact a sweet revenge by running through the compound yesterday with a now wholly unfeigned enthusiasm.

To get into the building back in March, you had to queue up to have your bags examined by scanners, to pass through metal detectors, and submit to body searches. Nato bombers struck highly specific targets in the compound some six times after its campaign started in March, saying that they were attacking "command and control" centres operated by the regime. Libyan officials persistently denied such installations existed, while being careful to allow visiting journalists to see only selected buildings that had been struck.

In appearance, Bab al-Aziziyah is from the inside a strange mixture of forbidding military barracks, regime headquarters and-almost-holiday village. Reputedly, Gaddafi at one time lived in a Bedouin tent in the compound's park, dotted with palm and olive trees, from which at night you can see the lights of the Carinthia and (long empty) Marriot hotels. The persistent rumour now is that he is hiding somewhere in a warren of underground bunkers at the site.

There were banqueting and state reception rooms, and a large library where, Gaddafi officials claim, the dictator once entertained Tony Blair. But of course, the dominant monument the minders most wanted you to see was the House of Resistance, the carefully preserved ruins of the multi-storey building semi-destroyed by Reagan's jets in 1986, the emblem of Gaddafi's seemingly permanent capacity to resist onslaught by foreign powers.

In some ways the overrunning of Bab al-Aziziyah is as potent and telegenic a symbol of the end of a dictatorship as the famous toppling of a statue of Saddam Hussein in a Baghdad square on 9 April 2003. But just as many Iraqis continued for weeks afterwards to worry that the real Saddam might somehow still return to re-impose his power over his people, so too the citizens of Tripoli, justly celebrating as they were last night, are unlikely to feel truly secure and liberated until they know for certain the fate of the man who has dominated every aspect their lives for more than four decades.