The bloody assault by terrorists on the heart of the USA has shocked the world.

Its sheer scale and audacity has numbed every country. After all, if it was America yesterday, it could be the UK or France tomorrow.

What these suicide bombers have done is strike at the heart of capitalism by destroying the World Trade Centre in New York and at the heart of American military might at the Pentagon.

They have caused huge loss of life among innocent people.

The USA is the mightiest country in the world. It is also unused to terrorism, unlike the UK which has suffered in the last 30 years from outrages emanating from conflict in Northern Ireland.

America was shocked by the Oklahoma bombing but this latest attack makes that pale into insignificance.

Yesterday's attacks were the biggest assault on the USA since Pearl Harbour, which brought the USA into the Second World War.

The world has changed since then and the country is more vulnerable because of the build up of weapons and the availability of fast planes.

America is not at war, nor does it intend to be. Its role in world affairs in recent years has been as peacemaker in disputes ranging from Northern Ireland to the Middle East.

The motive for these shocking attacks is as yet unclear, but it seems likely that they were as a result of tension in the Middle East where there has been loss of life in feuds between Israelis and Palestinians.

This carnage in America shows that no major city is safe from terrorism. In Brighton, people are only too aware of that after the IRA bombing of the Grand Hotel which killed five and injured many more.

At the end of the month, the Prime Minister and Labour visit Brighton for their conference. Security will be irksome but it is essential to preserve the lives of politicians and democracy itself.

There will be renewed concern over the anti-globalisation campaign planned to coincide with this event. Hopefully, common sense will prevail after such awful scenes across the Atlantic.

Tony Blair showed statesmanship in abandoning his prepared speech to the TUC when he was in Brighton yesterday. He and other leading figures from all parties quickly realised this was far bigger than any argument over private and public services.

Most people had a similar reaction on hearing the news wherever they were. It made their own personal squabbles and difficulties seem minor by comparison.

What America and the rest of the democratic world must do is not let the terrorists change its way of life.

Yesterday showed how easy it is for a few fanatics to cause death, mayhem and destruction on an enormous scale in the most sophisticated country on this earth.

By contrast, democracy is a fragile flower which takes years to cultivate but which is precious for the world.