Seems easy in the abstract, maybe not as easy in reality. You’d think there’d be no qualms after, he made the deliberate choice, not you.Not everyone can bring themselves to pull the trigger when they should. And some can never get over it when they do.
Worked with a guy that had 15 years on the job, great cop, top notch investigator. One night he got in a shootout with an armed robber. The armed robber missed, he didn’t. He quit a week later. He just couldn’t deal with having to shoot someone. Not even when he had no alternative.