be found. Nonviolence Some pacifists follow principles of nonviolence, believing that nonviolent action is morally superior and/or most effective. Some however, support physical violence for emergency defence of self or others. Others support destruction of property in such emergencies or for conducting symbolic acts of resistance like pouring red paint to represent blood on the outside of military recruiting offices or entering air force bases and hammering on military aircraft. Not all nonviolent resistance (sometimes also called civil resistance) is based on a fundamental rejection of all violence in all circumstances. Many leaders and participants in such movements, while recognizing the importance of using non-violent methods in particular circumstances, have not been absolute pacifists. Sometimes, as with the civil rights movement's march from Selma to Montgomery in 1965, they have called for armed protection. The interconnections between civil resistance and factors of force are numerous and complex. Types Absolute pacifism An absolute pacifist is generally described by the BBC as one who believes that human life is so valuable, that a human should never be killed and war should never be conducted, even in self-defense. The principle is described as difficult to abide by consistently, due to violence not being available as a tool to aid a person who is being harmed or killed. It is further claimed that such a pacifist could logically argue that violence leads to more undesirable results than non-violence. Conditional pacifism Tapping into just war theory conditional pacifism represents a spectrum of positions departing from positions of absolute pacifism. One such conditional pacifism is the common pacificism, which may allow defense but is not advocating a default defensivism or even interventionism. Police actions and national liberation Although all pacifists are opposed to war between nation states, there have been occasions where pacifists have supported military conflict in the case of civil war or revolution. For instance, during the American Civil War, both the American Peace Society and some former members of the Non-Resistance Society supported the Union's military campaign, arguing they were carrying out a "police action" against the Confederacy, whose act of Secession they regarded as criminal. Following the outbreak of the Spanish Civil War, French pacifist René Gérin urged support for the Spanish Republic. Gérin argued that the Spanish Nationalists were "comparable to an individual enemy" and the Republic's war effort was equivalent to the action of a domestic police force suppressing crime.