United we are strong, united we will win

Propaganda always precedes war: it is important that people are capable of imagining the death of the enemy before the face-to-face encounter. Then, once war begins, converting fear of the enemy into hatred is central to maintaining high morale. On some occasions, truth has a place in propaganda, but it is fundamentally incidental to the exercise.

Religion and war excite the propagandist more than anything else. It is no coincidence that the word only came into use in 1662, in the context of the missionary work carried out by the Roman Catholic Church's Congregation for the Propagation of the Faith. Only in recent decades, however, has propaganda become a major focus of historical study. The experience of the First World War was crucial in generating interest in propaganda. The systems of mass communications that arose during that war increased the demand for more information about international relations, facilitating the rise of government-sponsored propaganda.

At the same time, the war stimulated concern about manipulation of the "masses" by governments and the military, giving "propaganda" its bad name. In the years immediately after 1918, people realised the extent to which they had been duped by false atrocity stories deliberately spread by the government in order to shore up hatred of the "brutal Hun". In the following years, the rise of totalitarian regimes in Germany, Italy, and Soviet Russia also heightened interest in the use, and abuse, of propaganda. It was acknowledged that the comment by Joseph Goebbels, the German minister of propaganda, that an oft-repeated lie eventually would be believed, rang true even in parliamentary democracies. The distinction between propaganda as a repressive force and propaganda as a force for the understanding of politics and the encouragement of participation in the political process has been debated ever since.

One of the chief tools involves the demonisation of the enemy. During the Second World War, a great deal of propaganda was focused on portraying the Japanese as brutish. Allied troops were simply said to be exterminating "slant-eyed gophers" (in Admiral William F Halsey's words). By classifying the Japanese as inhuman, they became fair game. Indeed, the most popular metaphor used in propaganda at the time was that of hunting. Going to war was the equivalent of being "blooded". In battling the enemy, "boys" became "men". The enemy were "specimens" to be "bagged".

This abuse of language is central to the propaganda effort in all wars. In Rwanda during the 1994 genocide, Tutsis were described as "cockroaches", with the Hutus simply engaged in "bush-clearing". Hutus were ordered to "remove tall weeds" (adults) as well as the "shoots" (children).

Propaganda converted the language of mass killing into euphemisms. Killing was re-conceptualised as "action", "severe measures", "reprisal action", "rendering harmless", "evacuating", or "giving special treatment". It was not women or children who were killed, but spies, traitors, partisan fighters, and criminals. "War" became "conflict", "killing fields" became "free fire zones", and "killing civilians" became "collateral damage".

This demonisation and dehumanisation of the enemy was not dependent on lack of information. For instance, the Gulf War of 1991 was the most televised war in history. On a daily basis, people pored over the carnage from the safety of their sofas. In this war, the phrase "butcher of Baghdad" had great resonance, as did the tearful story by Nayirah, a 15-year-old Kuwaiti girl who described how Iraqi soldiers had tossed babies out of their incubators in a hospital. The fact that Nayirah turned out to be the daughter of the Kuwaiti ambassador, rather than a witness to atrocity, was never mentioned by President George Bush who repeated the story on numerous occasions. At times, the "free media" were remarkably willing to go along with attempts by the state to restrict what they reported.

During the Gulf War, for instance, the BBC reporter John Simpson lamented the fact that many of his colleagues were "demanding a curb on free reporting". The media's willingness to use the highly censored images given out to them by government bodies was equally questionable. This privileging of élite sources was even more pertinent during the Falklands war, when the media were severely rebuked if they even hinted at dissent about the legitimacy of the conflict. The propaganda of that conflict served to bolster Margaret Thatcher's regime by establishing the reputation of the "Iron Lady" as a "female Churchill". It was a propagandist's dream, with warships leaving the harbour to the tears of women, the waving of Union Jacks, and a military band playing Rod Stewart's hit, "I am Sailing".

Nevertheless, in wartime, propaganda works much better behind the lines where it is, for instance, effective in persuading men to enlist. But in the front lines, it falls flat. Military personnel are often struck by the ineffectiveness of propaganda in educating combatants about why they are fighting.

Soldiers resent being herded together for "pep talks", they are too weary to be stimulated by lectures on the evils of fascism or communism, and (preoccupied with the intimacy of combat) they sneer at political platitudes. Indeed, during all the wars of the 20th century, soldiers were aware of the discrepancy between the demonised pictures they had been shown of their foe while in training and those they encountered in battle. Combat experience taught servicemen to be distrustful about what they were told.

There was also an acknowledgement that the enemy was suffering in similar ways to themselves. In the words of William Clarke, who served in France during the First World War: "face to face with them you couldn't feel a personal hatred, they were soldiers like ourselves, manipulated by statesmen and generals and war-mongers. We were – they were – cannon fodder."

The writer is professor of history at Birkbeck College, London, and author of 'The Second World War: A People's History' (OUP) and 'An Intimate History of Killing' (Granta)