You would not "have pause" towards me (now) based on my opinion (even though that was the way it was expressed before). You would not feel guilt, nor remorse, but you would have a "clear conscience" and yet you expect to "feel bad".
While I would be doing my absolute best to NOT feel bad, you are however planning or expecting to feel that way. I think you would be too hard on yourself if you did that. If this ever happens to me, I would hope you would remind me not to do that.

Sober reflection is not the same as "feeling bad" -- unless that reflection finds that you made some contributory mistake that caused the death -- otherwise you are just an instrument the same as if these criminals had decided to jump out of a plane without a parachute -- not your problem.
Note that I would have pause if someone said they could have a clear conscience without sober reflection on such an event -- that is the only way we could possibly know if we had done the right thing, made mistakes, taken the best course in a bad situation to which we contributed, or had absolutely no choice.
I think Billy Jackson MIGHT have made one (or two) mistakes -- he flashed his money roll. That doesn't in any way make him guilty or responsible. As far as I am concerned he could have told them he had a million dollars in the apartment and didn't have a gun.
If they invaded his apartment with guns to rob and kill him then that was their choice. It is still a minor mistake to invite attack.
Although I think Joe Horn should be no-billed, maybe even given a medal, perhaps Joe Horn does have something to feel bad about -- Joe Horn chose to stop the robbery and to leave the safety of his home. Those two choices led proximately to his killing the two burglars legally. Were I Joe, I might feel a little bad about that. Guilt? Not really. Remorse? A little.
Billy Jackson? No way.
We all die (at least for now -- though give it another 25-50 years) -- the real question is how do we live.
PS> I might not have responded this time, but you did say you were enjoying the conversation. And I made the same point (separately) yesterday as you did on the abortion issue, unenumerated right derived from another unenumerated right, i.e., privacy, vs. a clearly protected and long acknolwedge right from before the Constitution was even considered. I have made that point frequently. Which is why I was wrong about Ginsberg -- she should now expect to hear 20 minutes of laughter anytime she claims there is a right to abortion. (No matter what anyone's belief on the subject). She and the other 3 have proven themselves hypocrites and intellectually dishonest.