By Paul Reynolds BBC News Online world affairs correspondent

As so often, science fiction came first.

In 1879, Jules Verne wrote a story called "The Begum's Fortune" in which a Frenchman and a German inherit the fortune of a relative, a Begum in India.

The Frenchman sets up a town called Frankville in the state of Oregon in the United States. The German also founds a town, Steeltown, nearby.

Hamas continue to carry out suicide attacks

The Frenchman's town is an ideal community (Verne was French of course). The German, however, makes a large gun and plans the destruction of Frankville at one blow.

To cut the story short, when the gun fires, the shell goes so fast that it misses Frankville and goes into orbit. It is still there - so they say.

Civilian targets

Jules Verne had identified the desire of a "terrorist" to hit an enemy population and cause the maximum damage possible.

Attacks on civilians are not new. The very word "terrorist" implies that civilians are put in fear, though it must also be remembered that one person's "terrorist" is another's "freedom fighter".

The primary purpose of terrorist groups is to create terror in the population at large

Colonel Mike Dewar, security analyst

But whether they are called guerrillas or terrorists or freedom fighters, armed groups have often attacked civilians. Many, though not all, wars against colonialism were based on them - by the FLN in Algeria against the French, or Mau Mau in Kenya against the British, for example.

Other groups like the Irish Republican IRA and the Basque separatist ETA have used a combination of tactics against both civilian and military or official targets, both in the homelands they seek to champion and in the strongholds and watering holes of their enemies. The Chechen rebels do the same, as we've seen in Moscow.

Indeed, the tactic of attacking civilians helps to determine whether a group is terrorist or not, according to Colonel Mike Dewar, a former British army officer and now security analyst in London.

"Your methods determine if you are a terrorist," he said.

Large scale attacks

"Targeting civilians is not a new phenomenon. The primary purpose of terrorist groups is to create terror in the population at large. The military should not, by definition, be terrorised."

Civilians were the victims of the Tokyo sarin gas attacks in 1995

What is new perhaps is the scale of the attacks on civilians. Part of this is a product of technology.

"It is easier to get hold of explosives. There are better communications. Someone invented the car bomb. Somebody thought of flying planes into buildings," said Col Dewar.

Just as civilisation has progressed, it seems, so has terrorism along with it.

What is also new is a shift from a local and particular event to a wider, even the global, arena, according to William Hopkinson, a former senior official at the British Ministry of Defence and an Associate Fellow at the Royal Institute for International Affairs in London.

"In earlier conflicts, civilians in one place might not have been safe. Now the threat is widespread and can crop up anywhere. The Bali bomb was a way of getting at the West not to further some local objective", he said.

Governments, these days, adds William Hopkinson, are better protected. "I suspect that the Dutch royal family does less bicycling these days," he remarked.This leaves civilian targets as an easier option.

Religious aspect

Another factor driving the modern style of terrorism is ideology or religion. Attacks from such sources have been daring and audacious. And cruel both to the victims and the participants. Al-Qaeda, with its emphasis on anti-Western Islamic fervour, is the prime example.

Attacks on civilians create terror in the population

Hamas, the Islamic specialist in suicide or martyr bombings against the Israelis, is another. Both attack civilians as an openly declared policy. Both rejoice in the deaths of their own.

There has also been a threat from cults. The Japanese Aum Shinrikyo let off sarin nerve gas on the Tokyo subway in 1995 in an apparent effort to precipitate a doomsday scenario in which it would survive triumphant. Civilians were the victims.

And ideology feeds on another modern phenomenon - publicity. The 9/11 attacks convulsed large parts of the world mesmerised by the television pictures.

"In attacks to destroy a civilisation," notes William Hopkinson, "attacks on civilians can contribute to wrecking the economy and producing paralysis."