Specialized warships are relatively recent in origin. They have always been expensive to build and need to be manned by crews with specialized skills. Their construction and operation therefore requires a great deal of the ruler's wealth. The earliest form of fighting at sea was probably piratical as opposed to political; even a pirate needs resources to get his start. The first navies may or may not have been pirate hunters but navies, by definition, cost more than individual ships. Whatever perspective one takes, fighting on water has cost more than fighting on land from the beginnings.