All caps on this one, as I consider it to be probably the root sin.
When you think of repressive, murderous regimes, there is typically one central figure around whom the whole machine rotates. Think Stalin, Mao, Caligula, Hussein...none of these guys quite achieves the level of old Adolph, who based a whole regime of repression and ethnic cleansing on the basis of his own, sinful, pride.
As I sat outside the coffee shop, drawing this picture, I had to explain to three different people why I was drawing a picture of Hitler. Each of them asked me about it in the same manner that they would ask why you were praying to the devil.
Not admiring him, just using him as an example.
It's amazing how, after over 60 years, the man's image still brings such a negative response. Hence the reason he became the ultimate Face of Sin for this series of drawings.