I've often thought it's pretty easy for "civilians" to sit in their office, their home, their dorm room, and second guess the actions of police officers, or in a similar vein, soldiers.
We ask these people to do a very difficult, dangerous job. We issue a weapon to them, give them the authority to use it when their professional judgment says they should, then put them in life or death situations.
It is the nature of their jobs that no matter how traumatized or frightened they may be by the position we put them in, they are essentially compelled to make a display of bravado, of "it's nothing, it's just part of my job", and go home and coach the kid's little league team eight hours after you had to shoot someone who was shooting at you.
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