Perhaps because of the rise of Christianity and Muslim religions. Who decided that if people that are not like them should be discriminated upon. Simple as that. When a group prospers, others are jealous and decide that instead of focusing their problems on themselves, it is easier to blame someone else.
But never again.
Reminds me of a story of the two fishermans. One was Jewish, the other Muslim. Both went fishing in the same area. The Jew took his time the day before, found a good stick that was strong, carved it with just the right angle, strung the string correctly, picked the right bait and prepared for hours before he went fishing. The Muslim picked up a stick in the morning, taped some string on it, found some bait in the kitchen and also went down to fish.
The Jew caught 10 fish, the Muslim 2.
And then instead of solving why he didnt get more fish, he blamed it on the Jew that he took his fish.
Sad.
I see it here in America all the time with people. Blaming each other instead of trying to figure out how to make yourself better. To teach yourself something new every day, so instead of drinking beer and watching a football game on Sunday and getting drunk, sit down, read a book and learn something one day. And stop complaining about everything.