During times of conflict or war, conventional moral and ethical codes concerning the treatment of others are often challenged. Political leaders often seek out methods to override their citizens' objections in order to gain support for their cause. One such method of public manipulation is called dehumanization. Dehumanization is the deliberate removal of sympathetic human traits when referring to members of an opposing ideology, race, political party or other source of conflict. Adolf Hitler's references to Jews as 'vermin' or 'rats' is one example of dehumanization in action.

Convincing an average citizen to commit a violent act or to murder a fellow human being is extremely difficult. Our moral code tells us that such acts are immoral and indefensible. However, through the skillful use of dehumanization, leaders throughout history have succeeded in doing just that. Once the enemy has been stripped of humanity and becomes an object worthy of punishment, the idea of mistreating or even destroying this threat becomes morally justifiable.

Dehumanization often begins with the removal of personal identification. A convicted criminal is issued a prison identification number, for example. This form of dehumanization allows the guards and other authorities to maintain an impersonal relationship with inmates. This practice of dehumanization is also used by military prisons to maintain a feeling of superiority over captured enemy combatants. Viewing the enemy as a human being may compromise a soldier's ability to interrogate him or her later.

Dehumanization methods can also be seen in other controversial areas. Those who support the rights of women to seek abortions, for example, rarely use the words baby or child in their literature. Using more clinical terms, such as fetus, could be seen as an effort to dehumanize an important element of the issue. Conversely, pro-life supporters may use dehumanization methods to reduce the staff members of a health clinic to uncaring baby killers. Dehumanization as a propaganda tool can work both ways.

Another example of dehumanization in action occurs during media coverage of wars or conflicts. The enemy forces are often described as extremists, rebels or terrorists, while friendly forces are described as troops or freedom fighters. Dehumanization allows the public to override their natural aversions to conflict by perceiving their enemies as inhuman. Dehumanization tactics also tap into a person's innate prejudices, such as by creating the character of the "Muslim extremist" or the "Jewish threat". It is far easier to justify the annihilation of a caricature than an actual race or religion.

Dehumanization is an effective propaganda tool when used skillfully. In the case of capital punishment, for instance, details of the convicted prisoner's crime are often given more media attention than details of his or her personal life before the act. As long as the public continues to view the Death Row inmate as an inhuman monster, it is relatively easy to permit the execution to occur. Dehumanization succeeds when average people with average morals and ethical principles no longer see the person behind the label.