It's morning in west Belfast. There's the clink of the milkman on his rounds. Hark the squealing of tyres as eight armoured vehicles rush towards a certain home. If you cock your ears, you'll hear the hearty cry of the lesser-spotted Police Service of Northern Ireland man: "Get up you Fenian bastard!"

Once again, Bobby Storey's house is being raided. It's nothing new, and as a senior republican and potential assassination target, his home is heavily fortified. He wakes up, turns to his partner and asks, given the circumstances, if she would make him a cup of tea.

By now the PSNI are beating at his front door. Officers get a ladder, and climb up to his bullet-proof bedroom window. Storey stretches and ambles towards the shower. The clamour increases. Neighbours come out to offer spontaneous suggestions and advice to the PSNI about the efficacy of the raid. Storey towels himself, dresses with care, and trots down the stairs.

At last, the reinforced steel frame of the door creaks and yields to the PSNI's mini-battering rams. But when the officers get into the hallway, they see a giant, cast-iron gate blocking their progress. Storey thanks his partner for the cup of tea, sits down at the table, and, in a matter-of-fact tone, informs the snarling PSNI officers through the grille: "You'll need an angle-grinder for that." He takes a sip of tea.

Forty minutes later, the police produce a cutting machine and attack Storey's gate. When they are about two-thirds of the way through -- and Storey has finished his toast and is bored watching them -- he leans forward with the key and opens the gate. He is dutifully hauled away to the interrogation centre, where he tells his inquisitors precisely nothing for 48 hours. He is released.

For Belfast people, Bobby Storey's nonchalance and fearlessness is part of his charm. Being blond, six-foot-two, trim, good-looking and highly intelligent also lends him authority in the neighbourhood. But it is his day job that makes him a hero to nationalists across the North.

For Bobby Storey is the best spymaster the IRA have had since Michael Collins.

He learned as a young man in the H-Blocks that good intelligence was a priceless commodity. For many months he acted as a model prisoner, all the time gathering the knowledge essential for the spectacular 1983 escape by 38 men.

On the outside, Storey continued his work. He built up a network of people in positions to pass on potentially useful information. He was able, the British now believe, to examine the itemised phone bills of top RUC officers such as Sir Ronnie Flanagan -- noting with equal interest professional and non-professional liaisons.

Storey's MI5 adversaries have also been forced to conclude that he planted agents in an insurance company that dealt with RUC and British army personnel, and a travel agency used by Diplock court judges.

But most impressive of all is the suggestion he was behind the robbery of computer files and documents at Castlereagh earlier this year, and has obtained the names and addresses of all of the North's Special Branch officers, their informers, and prison officers.

The British regard this as the biggest intelligence disaster in Irish history, and have already spent stg£20 million helping their people to move houses.

But republicans have a different perspective. They know that, while the IRA has no intention of reverting to the war, some MI5 and Special Branch officers have long wished for the peace process to break down.

It is clear to most observers, for example, that the persistent loyalist attacks on the nationalist enclave in north Belfast, which are being permitted by the PSNI, represent an attempt to provoke the IRA into action.

In this context, the fact that the IRA has such potentially devastating intelligence information is actually a powerful incentive on Special Branch and their informers to keep the peace.

Or, as the Sunday Telegraph put it last April in response to the Castlereagh robbery:

"The war is over. And the IRA has won it."

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Facts show Stormont is riddled with unionist spies