Speculating about the future is fun and has proved to be the basis of many works of "science fiction" and other literature. Some projections however, are used to drive strategies and raise concerns that government agencies might have to address. As the cliche goes, "the only sure thing is change."
One group that engages in speculation (driven by observed trends) is the National Intelligence Council which, on occasion, puts out a publication discussing the future. The latest edition follows. As you read over it, you might ask, "What did they get right?" "What did they get wrong?" and "What did they leave out?"
It might also be useful for you to read this Chatham House prepared report (pdf format) US National Security Impacts of Natural Resources in 2020, 2030, and 2040.
Read those things and you will have done a day's work.