The number one export of all industrialized nations is weapons. While I find this reality to be appalling, it’s certainly not anything new. From the beginning, one of the first things people specialized in was the technological advancement of weapons… of more effective and efficient ways to kill. We did start out, after all, hunting and gathering to survive. When we started exploring, we started conquering. While I’m not sure that answers your question, learning the history of how things happened helps to explain why things are the way they are now.
There is a very good documentary I watched recently called, Guns, Germs and Steel, that is available free online:
http://topdocumentaryfilms.com/guns-germs-and-steel/
I’m sure you will enjoy it, and gain some insight and perhaps answers to your question.