Sorry but i am having another confusing theory based on your previous reply.
As every action has an equal and opposite reaction. What if while you are here and all the time runs in parallel, someone reading your post prevented the WW3 from happening in 2016. Keeping in mind you are still here in 2015, but the WW3 is stopped by someone from govt or secret service who read your post. Without WW3 in 2016, future changed, you were never appointed by the military, which further zeroed your chance here back to 2015. Then how you are still here, even if you still exist here and you return back next year to 2040, there would be 2 you's in future(one already existing who never went to past and the second is you yourself whp returned from past).