“Wouldn’t it be dreadful if some day in our own world, at home, men start going wild inside, like the animals here, and still look like men, so that you’d never know which were which.”  -CS Lewis, Prince Caspian

 

People have a tendency to wallpaper over times and places with which they are unfamiliar with a  kind of light blue color.  "Oh that tribe I know nothing about?  Sure maybe some of them were mean but by and large I bet they were nice."

 

In some cases the wallpaper is covering a horrible infestation.

 

Consider the not-atypical Roman conquering of Carthage.  How was it different from the conquests of Hitler?  The past WAS Hitler.

 

The quarrel is begun... In such a strait the wisest may well be perplexed, and the boldest staggered. The circumstances are in a great measure new. We have hardly any land-marks from the wisdom of our ancestors, to guide us. At best we can only follow the spirit of their proceeding in other cases.  –Edmund Burke, 1770 describing a conflict between the King and the House of Commons