We must ensure that the technology we develop will aid in war fighting, not just in reducing manpower. There are people behind those machines, and they are what will win the wars.
Manpower always has been, and will be, recognized as the critical element in war fighting. Technology can improve our methods, but human input is irreplaceable. Automation cannot win a war.
Since the first crude vessels were pushed off the shoreline, manpower has been a concern. The canoes that transported Native Americans in search of game were not necessarily designed for six or eight men, but that is how many were required to get the vessel safely upriver in potentially hostile waters. The canoe could have been propelled by fewer, but the aft lookout would have had to man a paddle rather than stand his security watch.
It is no different in the modern warships of the U.S. Navy. To operate a ship effectively and efficiently, a certain number of watchstanders is required. We continue to have drivers, cooks, deck hands, engineering watches, and lookouts. We can accomplish our mission with fewer people, but at what cost?