Once of the most interesting things you discover when you read the archives is that lost of things we consider obvious today, was not at the time.
One of those is the usefulness of airplanes at the start of WWI, proven at the end, and the usefulness of tanks at the start of WWII.
The fact tanks were bad weapons at fist, bulky, difficult to operate, slow,low range(compared with big cannons) easy targets, and no ability to cross difficult terrain.
This was improved in an incredible way, for example tank suspension improvements rendered the Maginot Line obsolete when finished.
Lots of people in the army were against change. Making tanks were very expensive, they needed fuel, and they genuinely considered money was better spent on other things.
I am talking about power imbalance that made Poland completely obliterated by Germany and URSS within four weeks.
That Poland was "eaten or breakfast" because it was not prepared was a fact. Poland had not the industry to face Germany in a different type of war.
For me that proves that people could be inherently Evil while not realizing about what they are really doing(until they suffer from it).
For example, at the start of the WWII killing and abusing for the Germans and Japanese was so easy because there was such a power imbalance, like in the experiment with guards weapons,horses against tanks in Poland in WWII, that they actually abused and killed without actually thinking about it. They were Evil, but most of them did not really knew at the time, because all the propaganda they heard and so on(radio told them they were being heroes).
It was only when they started to loose that they understood what they had done to others, because they started being on the Evil receiving side.
Today you see this power imbalance in Iraq, any American soldier could kill 100-200 people from the other side before one American dies. So they don't really think about this until a terrorist attack kills 10-20 people in the West. Control on the media means the thousands of people dying in Iraq is not displayed on TV, so it does not exit.