Modern self-defense doctrine only allows potentially deadly force to be used to protect innocent life (as opposed to property), and only when there is no reasonable alternative such as escape, and only to the extent reasonably necessary (e.g. 1 or 2 shots rather than emptying your mag and then re-loading).
While I have a lot fewer complaints about the Castle Doctrine (limited to your dwelling) than I do the Stand Your Ground Doctrine, it still troubles me that both seem to gloss over the need for the threat to be against innocent life, and the use of deadly force only as a last alternative.
This is one of the most interesting aspects of this subject, and I've been thinking about it for the past couple of days. I'm pretty sure I'm opposed to SYG. But as to the Castle doctrine...
I already stated that it is quite reasonable, it seems to me, to be in a state of fear for your family the minute you are aware of an intruder at 2 am in the morning on your property, and that it is also quite reasonable to remain in that state of fear until the threat has been removed. That being the case, it follows that placing the same sort of restrictions on justifiable self-defense that we would in a confrontation elsewhere (as I would in the Zimmerman case, for example) seem burdensome here. Simply put, I don't believe a homeowner, who is in a reasonable state of fear for his family's lives, should have to take the time to be responsible to determine whether the danger is real or not. Not at that time of the night.
If that means that ultimately I am arguing for the right of homeowners to execute trespassers, then so be it.