I asked this same question back in 2013 and there was almost no interest in the topic at that time.  
https://talk.newagtalk.com/forums/thread-view.asp?tid=357156&posts=10&highlight=cop&highlightmode=1#M2818048
Funny how a few years and drastically lower prices changed the attitude as evidenced by the recent thread.  
My opinion hasn't changed since then, have these prices and increased production changed anyone else's minds? Or caused you to give it more attention?

Worldwide, It will come down to which government strangles their farmers the least, and which can afford to subsidize them the longest before going bankrupt themselves.  
Regionally, COP and climate(formerly known as weather) patterns.