I will take a shot at it.
I was alone in the desert by Tubac, Arizona (southern portion of the state) (Probably a place you like or feel comfortable in
). Thre sonoran desert was more green than I have ever seen it in my life(Your life is happy and you are content with yourself
). Some movement to the south caught my attention and I looked a saw thousands apon thousands of tanks driving in a straight line (Something was happening that causes you great alarm because it has the power to annihilate not only you but a lot of people
) . I took off running but evetually one of the tanks caught up to me (you feel threatened by the event and take the precautions you were capable of with the resources you have but it is not enough
). Now these weren't like normal tanks because the riders set on top like in carriages (The danger was all knowing and could see in all directions and were controlled by humans
) but they still had the big cannons and whatnot(The humans had the power
). Anyway, riding on top of this tank was a mexican man and his pregnant wife and perhaps a young child or two( the threat was from someone similar to you or what your ideal is, you begin to realize this may not be a threat to you after all
). The man looked at me for a while, reached into his clothes, pulled out a gun and..... handed it to me (You realize this was not a threat to you after all and was really something powerful that is here to assist you
after this I turned and continued north towards my family at which point the dream ended.(you continue to pursue the course which will lead to your happiness with your family)
Seems to me you were once somewhere in your life where you thought you were happy but you were alone and something very powerful came your way. This power or occurrence reminded you of how vulnerable you were and you got scared. At first you were afraid of that power, but when it arrived it reminded you about your family and that that is where you were going to find happiness. Then you were given the chance to reconcile with your family and you took it.
Hey I am no Joseph, but I thought I would give it a shot.