In a corner of St James’ Square in central London, there stands a small memorial. It is to police Constable Yvonne Fletcher who was shot dead while policing a small demonstration of Libyan exiles outside the then Libyan Embassy in 1984. Her assassin was believed to be a Libyan diplomat, and as a result of her murder, the Embassy was closed and all of Libya’s diplomats were sent packing.

I thought of the incident today as Libyan exiles demonstrated outside the new Libyan Embassy, a stone’s throw away from the Al Jazeera’s Broadcast Centre just off Hyde Park Corner. How often had I walked past that Embassy, and how dangerous it might now be for the demonstrators today?

Since 1969, when a young army officer by the name of Gadaffi, toppled the decadent regime of King Idris, the Libyan regime has been a by word for unpredictability and terror tactics. That Gadaffi is himself mercurial and unpredictable is a statement of obvious fact, and having reported from the Libyan capital of Tripoli on three occasions, I can testify to the weirdness of the regime. For a start, one of the main exhibits in the national museum in the centre of the city is the beaten up Volkswagen beatle Gadaffi drove across the desert on his way to ferment his revolution. All across the city are huge portraits of the Libyan strong man dressed in various outrageous garb. Libyan TV News is dominated by Gadaffi, once again sporting all manner of outlandish uniforms. For some years now, I have believed that the crazed Gadaffi is probably gay.

At one level there is something faintly amusing at the Ruritanian madness of it all. Except that Gadaffi’s hired thugs didn’t just shoot a British policewoman, but routinely funded the IRA back in the days when it bombed its way across Ireland and Britain. Gadaffi, in his time, has backed all manner of terrorist groupings, even though perhaps one of the most memorable outrages, the Lockerbie bombing may not have been carried out by the Libyans.

Gadaffi’s hired thugs are now killing Libyan civilians. The vivid pictures we have seen from Benghazi show just how far he and his henchmen are prepared to go. This isn’t the first time Benghazi has protested, but this is the biggest and most visible revolt against the Libyan dictator’s 42 years in power.

All of this begs a very obvious question: what on earth did countries such as Britain and Italy think they were doing when they began to cultivate Gadaffi a few years back? With unseemly haste Messrs Blair and Berlusconi rushed into the Libyan dictator’s embrace, seemingly ignoring all that had gone before. Libyan exiles warned at the time that they were supping with the devil.

As with Tunisia, Egypt and Yemen, the response of the West has been slow and unsure. There is absolutely no excuse now for not holding back – especially when it comes to the organised butchery of his own people by the vile Gadaffi. Should the regime succeed in stifling the current revolt, this time there must be no quarter. Only absolute isolation will do – and a very immediate and real threat that Gadaffi and his henchmen face trial at the International Criminal Court in The Hague.