War is an intense armed conflict between groups of people (states, governments, societies, or paramilitary groups such as mercenaries, insurgents, and militias). Total war is warfare that is not restricted to purely legitimate military targets, and can result in massive civilian or other non-combatant suffering and casualties.

War usually results in significant deterioration of infrastructure and the ecosystem, a decrease in social spending, famine, large-scale emigration from the war zone, and often the mistreatment of prisoners of war or civilians.

Naturally, the common people don't want war; in any nation. Wars occur when leaders with a psychologically abnormal disregard for human life are placed into power. War is caused by leaders who seek war. Such leaders most often come to power in times of crisis when the populace opts for a decisive leader, who then leads the nation to war. (Whether it is a democracy or a fascist dictatorship or a Parliament or a Communist dictatorship... the people can always be brought to the bidding of the leaders. Leaders tell them they are being attacked and denounce the pacifists for lack of patriotism and exposing the country to danger. It works the same way in any country).

One of the main reasons for wars is expanding populations and limited resources. Populations always increase until they are limited by war, disease, or famine.

On a global scale, the time since WWII has been unusually peaceful.

In our modern days, because of our knowledge, technology and globalization of trade, we see most of the problems on a global scale and have reduced wars drastically. But when they occur sometimes, it will be a ‘total war’.

Modern humans have made business a major part of survival. They see war as a great business opportunity. Arms trading have become the foremost business over the years. Technology is helping us to build increasing sophisticated and destructive weapons.

Most of our national governments are increasing their spending on their armed forces in the name of Defense of their Nation. But they can also be used for attack of other nations.

Peace and Love are the forces that move the world. But I think, War is the most potent of all forces of historical change.

Historically, all over the world Empires and civilizations have risen and fallen. Most of the time, the final fall of an empire is due to war with outsiders. The victorious outsiders then start their own civilizations. They also assimilate some of the culture from the vanquished civilizations. This makes their civilization better than the previous one and helps in the growth of humans.

I think that when the next global war breaks out, it may end our civilization, but as history has shown us, the survivors may build a new and better civilization.

In nature, there is always a constant battle for survival, which helps in evolution of species. It is different with humans, but even they have to constantly evolve to survive as a species.

So, War is a necessary evil for the Growth of Humans.