War is the driving force behind human civilization.
The very thing that threatens to destroy civilization is what drives civilization to improve its technology and social development. It is a sad fact that from the art of killing other humans, we have derived most of the tools and social organization that make up our societies.
The connection between war and the advancement of learning was noted even in ancient times. The ancient Greek writer Aristophanes stated:
"Yet, certainly, the wise learn many things from their enemies; for caution preserves all things. From a friend you could not learn this, but your foe immediately obliges you to learn it. For example, the states have learned from enemies, and not from friends, to build lofty walls, and to possess ships of war. And this lesson preserves children, house, and possessions."
There is much truth embedded in this simple statement: cities learn how to build walls from their enemies. They learn because of war. Now of course we no longer build walls around cities, but this is because the art of war has made walls obsolete. In other words, the science of war has led to siege engines, counter siege engines, explosives, artillery, airplanes, which have made walls and fortifications useless.
But the truth is still there: cities learned to build walls to protect themselves against attackers. To build walls, the people learned to quarry rock, they developed masonry, they developed the social organization to organize and command groups of people to get the rocks, shape them, and erect them. In so doing, cities learned geometry, mathematics, architecture and so on. And the attackers, those who would breach the walls learned from their enemies too: they learned to build siege engines, and learned the principles of ballistics, of mathematics. They learned how to lay siege to impregnable fortresses by surrounding them and starving them into submission, and in so doing they learned how to keep large armies in the field around the cities and how to supply them with provisions for a long campaign.
To attack a city, people learned how to organize and move large numbers of men and camp followers. They developed logistics: wagons to move food end equipment, social organizations to draft soldiers, institutions such as the army to train them, chain of command, communication systems, maps, and so on. And this pattern continues to the present day. Our present civilization reaps the bitter fruits of a thousand wars, most long forgotten, that have been the true mother of invention.