Nearly fifteen years ago, when I was working in our embassy in Washington, I was introduced to a serving American general at a reception. This was at a time when the Berlin Wall had just been pulled down, and the mighty Soviet Union was in the midst of a meltdown.

"Well, general," I said. "Now that your cold war adversary has collapsed, I suppose you'll be looking for other enemies. I hope Islamic radicals aren't on your list."

I was half-joking, and the general's hollow laugh indicated that he didn't consider my comment very funny. But even back then, I was aware that huge military machines do not demobilize bust because there is no current threat to justify them.

For centuries, people have been frightened by their leaders into supporting armies which are then used to feed the egos and ambitions of dictators and despots. But democracies are equally capable of this sabre-rattling. As Hermann Goering put it at Nuremburg during the war trials after the Second World War:

"People don't want to go to war... But, after all, it's the leaders of the country who determine the policy and it's always a simple matter to drag the people along with whether it's a democracy or a fascist dictatorship or a parliament or a communist dictatorship... Voice or no voice, the people can always be brought to the bidding of the leaders.

That is easy. All you have to do is tell them they are being attacked and denounce the pacifists for lack of patriotism and exposing the country to greater danger. It works the same way in every country."

This is as true today as it ever was. After the cold war ended, there was a brief burst of optimism when many people sincerely believed that a new era of peace and prosperity was just over the horizon.

Without the destabilizing superpower rivalry, smaller nations would no longer be pawns in a global power struggle, and thus be able to devote their resources towards solving the more pressing problems of hunger and want.

Welcome to reality. These last fifteen years have probably seen more bloodshed and mayhem than any comparable period since the Second World War. The genie of nationalism, long suppressed by communist ideology and power, emerged from its bottle and has caused a succession of wars across Eastern Europe.

Tribalism has wreaked havoc across much of black Africa. And Islamic terrorism, rooted in militant Wahabism and the anti-Soviet jihad in Afghanistan, has led to a grotesque distortion of the perception of Islam, apart from causing a growing backlash in the West.

But leaders exploit fear among their citizens, magnifying threats in order to whip up hysteria and a strident patriotism that encourages intolerance. In his Oscar-winning documentary "Bowling for Columbine", Michael Moore showed how ordinary citizens are manipulated by the media as well as politicians into an irrational fear of largely imaginary violence, mostly from blacks.

They go out and buy guns in prodigious numbers, and are prepared to use them on the slightest pretext. This is why the number of gun-related deaths is higher in the United States than any other advanced society.

In the past, many nations have used specific communities as scapegoats for their problems. Jews were particularly popular as targets for persecution in much of Europe. Russia and Poland have a long history of pogroms.

England banished them in the medieval era. Nazi Germany tried to exterminate them through the Holocaust. Hate-mongers in all these countries (and more) have accused the Jews of a long catalogue of invented evils, ranging from war-profiteering to horrid rites which include the killing of Christian children. But other groups have also been demonized and subjected to all kinds of horrors. In the last few years, the unfortunate Tutsis have been slaughtered in their hundreds of thousands in Rwanda as well as in surrounding countries.

Their only sin is that they are slimmer and taller than the majority Hutus. But they have been blamed for snatching the rights of the majority, as well as being 'foreigners'.

This fear of the outsider is exploited by cynical politicians who magnify and manipulate natural phobias and prejudices. Military propagandists use these base sentiments to whip up hysteria in their preparation for war.

In this hyped-up state, people are willing to believe anything their leaders tell them. Thus, when Yahya Khan and his coterie told us that Bengalis wanted to break up the country and were heavily influenced by Hindus, most people in West Pakistan swallowed this line without asking any questions.

Any psychologist will confirm that people behave irrationally when they are fearful, and feel threatened. And politicians are quite capable of using mass psychology to further their ends.

In such a scenario, the herd instinct comes into play as individual fear feeds into the collective psyche and is greatly magnified. Acts of violence that would have been unthinkable to a normal person suddenly acquire legitimacy and even social sanction when committed by a mob. And when this mob hysteria is given the encouragement and blessings of the state, we get the scenes of horror that are now all too familiar. But why should a thinking individual surrender his ability to tell truth from fiction? Why should he fall prey so easily to state propaganda?

In truth, it is generally easier to go with the flow than resist the call of the mob. Despite our thin veneer of civilization, we remain bound to the tribe. "My country, right or wrong!" is still the rallying cry of patriots around the world.

We have not yet evolved to the point where we can openly disagree with the majority and take a stand. Partly, this timorous attitude is due to our fear of being ostracized by the tribe. But mainly, when somebody weaker than the majority is the prey, the atavistic pack instinct in us calls for blood.

This is the kind of behaviour that is prompting ordinary, decent Americans to support Bush in his war on Iraq, a country that had nothing to do with 9/11. But American blood is up, and a majority still believes that Saddam Hussein was somehow behind the attacks on the Twin Towers.

Out of pure fear of more terrorist attacks as well as a burning desire for vengeance, millions of Americans support Bush, and may well give him the 'four more years' he is so desperate for.