Which is why the extraordinary new Hartcliffe Town Hall (one of 14 built over the past nine years on the edge of the city) resembles nothing less than a fortress. Not just any fortress, but the kind you might expect to find in a Judge Dredd comic-book caper, or else in the war-zone graphics of some killer-zombie computer game.
From the outside, this least civil looking of civic buildings seems as tough and as defensive as the prison wire that protects it from unwanted intruders (prison wire is normally used to stop criminals from getting out; at Hartcliffe it is used to stop them from getting in).
Inside, the town hall is warm, colourful, inventive and (stand-up rows aside) friendly. And, believe it or not, the kids love it. Or seem to. They have taken to calling it "Symes Castle" (because it looks like a castle and stands at the top of "Symes", the local Fifties shopping parade).
This enthusiasm matters, not least because local youths have been known to drop firebombs into town hall letterboxes. Over the past 15 years, children have learnt the Thatcher mantra: private buildings good, public buildings bad, and set on the latter like a pack of hyenas. Local schoolchildren, however, have been encouraged to feel a part of this modern fairy-tale fortress because they have been involved in its making.
With a little help from Vizibility Community Arts, a Bristol public arts initiative, pupils of Hareclive school have designed and helped make the steel gargoyles that guard the parapet of the town hall as well as the Gaudi-esque mosaics that colour the building's entrance.
This community involvement has been rewarding. There is, six months on from the building's completion, little sign of vandalism and only a token display of spray-paint graffiti.
"This is pretty encouraging," says Keith Hallett, "because the reputation of Hartcliffe has been rock-bottom since the Bristol riots of 1992. The area has suffered from a siege mentality. Look around you."
Half the shops are empty, the rest permanently protected by steel roller- blinds. The banks have pulled out altogether. Unemployment among young men is high and there is a problem with petty crime and drugs.
On the surface, Hartcliffe seems an unlikely place for a riot. Its houses may be dreary, but at least they are houses and not appendages of some vast local authority estate. They stand with their backs to the sheep- studded magnificence of Dundry Hill, looking almost picturesque on the approach along the arterial road that leads here from Bristol city centre.
But, when you come close, you realise that Hartcliffe, despite its near rural location, is rather like one of the feared and loathed former South African townships. Like the blacks and coloureds of Cape Town and Johannesburg, Bristol's poor whites were bussed out of the city centre and decamped in this (and its sibling) New Town-style suburbs.
Cut off from the city centre 40 years ago (the local, deregulated bus service is the usual mess), Hartcliffe offers little in the way of diversion, entertainment or excitement. Poor, white and segregated, Hartcliffe was much more volatile than it could ever have seemed to visitors, that is if it had any visitors.
"What we've tried to do," says Hallett, "is to turn grossly defensive building into exciting architecture."
There is no doubt that the architects have succeeded in doing this. On a shoestring too. This civic fortress cost just pounds 1.3m and was completed within 60 weeks on a fixed-time, fixed-cost contract.
The building looks as if it might have cost a lot more, but this is because its undulating natural stone front, mosaics and other decoration appear to be parts of some vastly substantial structure. In fact the building is really no more than a rapidly erected proprietary steel-frame, the gaps between uprights imaginatively filled.
Built in a rush, Symes Castle still looks rather gaunt from the outside, but plants are being trained to climb up and around the building and, with the addition of the gargoyles and mosaics, it is beginning to bed down into its prominent head-of-the-shopping-parade site.
Inside (the entrance drum is made from a steel agricultural silo; it has to be bullet proof as well as fire and vandal proof), the building opens up gently into a large double-height hall where 200 or so local people each day meet 65 representatives of the local authority housing and social services teams who are here to deal with their problems.
This is a quietly dramatic space, its soft colours contrasting with the out-of-context lorry and coach-building components the architects have used to fashion some of the interior details. Others are made of unpainted galvanised steel, neoprene or MDF. Sounds punky, yet the overall effect is neither gimmicky, nor pernickety.
The building needed a degree or warmth and invention, not least because the local social services department has to deal with many disturbing cases. It has already found that the interior helps to diffuse aggression and other outbursts. Interview rooms are almost jolly, a big change from the grim offices (low, suspended ceilings, aggressive fluorescent light, cheap carpets, horrid wall textures) found in far too many low-ranking local authority buildings.
One of the big surprises of the town hall, and another reason why it seems so approachable despite its bristling skin, is the courtyard, planted with trees, shrubs and flowers at its heart. This enjoys a curiously Mediterranean air, and serves to bring daylight and fresh air into offices and corridors facing its four sides.
Tough on the outside, soft on the inside, Symes Castle sounds a bit like a snail, a hermit crab or a hedgehog. Is this the windowless way that civic buildings are destined to go? Perhaps, but the imaginatively defensive architecture wrought here ought to remain a one-off; not because it is in any way wrong, but because its very individuality defies copying.
A curious postscript is the fact that two locals have told Hallett and Pollard that, should they win the Lottery, they would like them to design houses for them. It looks like the British are developing a siege mentality.