HELP! I just don’t get it….what am I missing on this one?

I have two law degrees — a JD and an LLM.  Despite that education….I have a question.  There is something I don’t get.

I have also tried lots of cases and many of them have been murder cases.

But in spite of the above, I do not understand the difference between ‘self defense’ and ‘stand your ground.’  I think they are one and the same.

Help me understand.  First, this is how I see it:

Self defense by its very definition means you can defend yourself.  If you run at me with an ax, I can shoot you.  That is self defense.  I do not have to run and hope you can’t catch me.   As I stand there and shoot you, I am standing my ground.

And note, the danger giving rise to a legal self defense must be ‘imminent’ — and the mere fact that it is ‘imminent’ means you can’t retreat.

Am I missing something?  I must be and I fear it is obvious but just escaped me.

Help me understand…