I can't see you living well with something like that on your conscience.

It isn't a shortcoming or a criticism. It just doesn't seem the sort of thing that would do well by you.

[The whole...killing thing.]

Some of us are well-suited for killing others, for better or worse. There's usually something that's been broken, with regards to people like that; it's rare that you find someone that's both suited to it and more or less intact. I don't think you're broken enough for that yet.