In creation God made mankind to live creatively and in peace. The Bible describes sin almost like a virus that has infected what is intrinsically good. It may infect individuals, groups, or even whole nations - you only have to read about all the misery and stored up hatred in the Balkans. The whole meaning and sense of life has been corrupted. Sin also has the capacity to multiply.
Hate breeds hate unless the cycle is broken by unconditional forgiveness.
So the history of many countries has been of cycles of violence and vendettas. People who have been kicked have a tandency to kick in response, but they aren't always fussy about who they kick in return. In many cultures vengenance is a way of life, e.g. in Corsica. He often presents his temptations in ways that look innocent or reasonable, but his aim is always to disrupt the wholeness or peace of God's creation. He implants the self-centeredness into people's hearts that works against God's purpose for our lives.