Buddhism's explanation, compared to all other philosophies, religions, theories, and logic, is most simple: Anger, avarice, and stupidity

http://www.cnn.com/2013/08/29/world/meast/syria-iran-china-russia-supporters/index.html

Please read the article and some or all of the 900 comments. It ALL boils down to avarice, anger, and stupidity. The answer is even more simple: Chant  Namu Myoho renge kyo.