Police and secret service plan a tight grip after protesters threaten action

The young police officer with a shaving nick on his chin was certainly erring on the side of understatement. "Let's just say it's a pretty big operation," he said, standing at a roadblock at the Lincoln Memorial. "Our attitude is simply that it's better to be safe than sorry."

The young police officer with a shaving nick on his chin was certainly erring on the side of understatement. "Let's just say it's a pretty big operation," he said, standing at a roadblock at the Lincoln Memorial. "Our attitude is simply that it's better to be safe than sorry."

And no wonder. Like everyone involved in the security operation, the careless shaver on duty yesterday while Latin heart-throb Ricky Martin and Cardiff schoolgirl Charlotte Church opened the celebrations for the inauguration of America's 43th President does not know quite what to expect.

They do know the ceremony will attract crowds of up to 750,000 people, all keen to catch a glimpse of George W Bush make the journey from Capitol Hill to the White House. They know between 5,000 to 20,000 of these spectators will be what the authorities politely term "rowdy", probably more than at any inauguration since 1973 when Richard Nixon was sworn in for his second term amid stone-throwing anti-Vietnam protests.

They are also aware that many protestors, such as those led by the Rev Al Sharpton, the National Organisation for Women and others who believe a Presidential election victory was "stolen" from them, have publicly declared their intention to make their voices heard as loudly as possible as the President is sworn in on Saturday.

"Our intention is to get as close as possible and to be non-violent," said Daniel Holstein, of the Justice Action Movement. "We expect to get just as close as the supporters." But the precise mood some protests might develop is impossible to predict. One clue might be the increasingly fractious mood over the confirmation hearing for John Ashcroft, Mr Bush's controversial nomination for the key cabinet position of attorney-general.

But the real spectre haunting those trying to ensure the protests are kept peaceful is the memory of the disturbances that rocked the World Trade Organisation meeting in Seattle in 1999 when protestors fought running battles with the police who were forced to clear the streets with tear gas.

The security services say they have been studying such events. "We have been planning these arrangements for several months and we have looked at every situation [such as Seattle] and made a critique," said Eric Harnischefeger, a spokesman for the secret service which is co-ordinating 16 law enforcement agencies.

The authorities believe they have left nothing to chance. The city's 3,600 police officers and 1,200 reinforcements from outside will line the parade route. There will be 1,200 Capitol police, responsible for security in the Capitol grounds, and 2,800 secret service officers. There will be baggage checks, manhole checks and snipers on the rooftops. All post boxes, rubbish bins and newspaper-vending machines have been removed, to deter bombers.

Some believe the ceremony will be trouble-free. Jean and Carl Peterson, who drove for 13 hours from their home in Wisconsin, were at the front of the queue for the opening. "The big deal is going to be the parade on Saturday," said Mr Peterson. "How could anyone disrupt it?" Not everyone is so convinced.