Irrational Human - War

Irrational behavior refers to actions or decisions that are not based on reason or sound judgment. It may be characterized by emotions or other psychological factors that influence decision-making, rather than logical or evidence-based thinking.

Irrationality often has a negative connotation, as thinking and actions that are less useful or more illogical than other more rational alternatives.

However, irrationality is not always viewed as a negative. Much subject matter in literature can be seen as an expression of human longing for the irrational. The Romantics valued irrationality over what they perceived as the sterile, calculating and emotionless philosophy which they thought to have been brought about by the Age of Enlightenment and the Industrial Revolution.

Dada Surrealist art movements embraced irrationality as a means to "reject reason and logic". André Breton, for example, argued for a rejection of pure logic and reason which are seen as responsible for many contemporary social problems.

Irrational behavior can sometimes lead to outcomes that are not in an individual's best interests, or that are harmful to others. Examples of irrational behavior might include making impulsive decisions, engaging in risky behavior, or failing to consider the long-term consequences of one's actions.

Humans are irrational. Our brains evolved to be intuitive, recency biased and fickle.

Most wars have been irrational in terms of means or ends or both together. This is because choices for war are influenced by emotions, ideologies, domestic politics, and the tyranny of history, as well as by the more rational pursuit of material and strategic interests.

Life Is Sacred

The pacifist position against war or violence generally is often based upon the deontological argument that all of life (or just all human life) is sacred, and hence it is immoral to ever act in a way which would cause the deaths of others or harms others.

War destroys communities and families and often disrupts the development of the social and economic fabric of nations. The effects of war include long-term physical and psychological harm to children and adults, as well as reduction in material and human capital.

Realist and other scholars commonly hold that rationally led states can and sometimes do fight when no peaceful bargains exist that both would prefer to war. 

So any war, is never really rational, as the cost always outway the benefits.