Margaret Thatcher said: "Life must go on as usual. Conference will go on."

At that very moment, somewhere under mountains of rubble, her right-hand man Norman Tebbit was fighting for his life.

Firefighters and paramedics saved him but his wife Margaret was crippled for life.

Five people died and 31 were injured in the IRA bombing of the Grand hotel in Brighton, 20 years ago this October.

This city, more than any other, has every reason to ask why it puts itself in the terrorists' gunsights.

Yet hardly anyone living here does.

Head of tourism Adam Bates said Brighton and Hove City Council had received only two letters of concern and these were about specific problems caused by the security operation.

He said: "We have not received any saying the party conference should be held elsewhere."

With four new hotels now under construction in the city, he pointed to the enormous financial and employment benefits party conferences bring.

Between £10 million and £15 million will ring through the tills of hotels, shops and businesses during Labour's visit from September 26 to 30.

He said Labour "clearly likes us" and will be back again next year.

In addition, the Tories, who have shied away from the city for several years, are planning their spring conference in Brighton between March 11 and 13 next year and may hold their annual conference here in the near future.

Mr Bates said party conferences were the shop window for the city, providing worldwide media advertisements to attract more events.

The price the city is paying for all this media attention and disruption is relatively minimal.

Kings Road will remain open. Russell Road car park will close. A new park-and-ride bus service will run from Brighton racecourse, with roads shut when and if necessary.

The Hilton Brighton Metropole hotel will once again be connected to the Grand and the Brighton Centre by a purpose-built bridge across Cannon Place.

Stop-and-search procedures will annoy some people but Sussex Police and the council say they will do their best to ensure the city runs as normal as possible.

The 1,000 residents and 100-plus businesses in and around the "island site" conference centre have been kept informed and their needs accommodated as far as possible.

Mr Bates said 13,000 jobs depended on the city's visitor-conference economy, one of the main reasons the city welcomes Labour.

The cost of security, once met by Sussex Police, is now covered by a Home Office grant.

There are no threats or intelligence reports suggesting an imminent terrorist attack but Sussex Police are taking no chances.

The £2.3 million Operation Otter includes armed police patrolling streets, 1,000 officers, and steel-encased barriers surrounding key buildings to thwart car bombers.

Although police would not comment, the RAF is likely to have Harrier jump jets on standby somewhere, ready to deal with any aerial attack.

All 16,000 delegates and visitors have been vetted and will be searched each time they enter the island site.

Chief Superintendent Jeremy Paine, in charge of security, said there were no specific threats but the possibility of an attack remained in everyone's minds.

He recalled the recent warning from Metropolitan Police Commissioner Sir John Stevens that it was not a case of if but when.

The absence of any opposition or lobbying among residents to shut the door on party conferences in the city could represent several things.

It could be apathy, a feeling of "take the money and run the risk" or a determination not to be bowed by the threat of terror.

It was a resilience spoken of by then Tory Party chairman John Gummer just hours after the Grand hotel bombing.

He said: "We intend to continue with our conference in exactly the same way we would have done had this outrage not happened.

"We shall do so because those who wish to interrupt democracy must be shown that whatever means they use must fail."

Douglas Hurd, then Northern Ireland Secretary, echoed his view when he spoke at the Brighton Centre conference: "There is a contrast here which we all must feel.

"A contrast between what happened in darkness a few yards away and a few hours ago.

"That work, in darkness, of killing and maiming innocent people and what we do here in the light of day.

"Democracy, which we have, will outweigh their bombs and bullets."