Gaining the necessary support to wage a war obviously involves some pretty serious tactics of manipulation, especially after traditionally learning that it is immoral to kill. When comparing wartime propaganda, specific patterns begin to emerge.
1) Trivializing and/or villainizing the enemy is essential. Often times the enemy is compared to vermin, and euphemistic terms are used to describe violence against them. Additionally, groups that are being defended are often portrayed as weak and defenseless. This makes war justifiable by because the nation waging it is defending those who cannot defend themselves, and is fighting an enemy that is less than human and therefore not worthy of consideration on a human level.
2) To reinforce existing prejudices. (see previous post)
3) To wage the war on humanitarian grounds. This is a tactic commonly used as the “humane” approach to war. Of course, those taking the anti-war stance do so on humanitarian grounds as well–in this case, the motivation of both pro and anti-war advocates is essentially the same, but this commonality is overlooked based on discrepancies in the solution.
4) To prevent the spread of unethical doctrines and fascism (Nazism, communism, Saddam Hussein and the Baathist party, etc.)
5) Preemptive attack–this has been especially common in more recent years, as justified by the U.S.’s bombing of “potential” enemies.
The list could go on, and note that these are relatively basic commonalities and patterns. But their repetition is worth considering.