Gaining an understanding of your enemy's background, capabilities and motivations is not a 'courtesy'. Rather, such knowledge is needed to achieve victory.
"If you know the enemy and know yourself you need not fear the results of a hundred battles."
You are making a fine point, but I think the spirit of your comment is quite different from the original from @williamle8300.
Your point a agree with on a big picture level, the war fighters and analysts and policy makers need to understand capabilities and motivation of the enemy. I'm not a war fighter and I don't believe it makes any sense for me or other Joe Average Citizen to empathize or understand a psychopathic foreign enemy. Understanding in this case won't get you far.
But also I do not feel inclined or obligated to afford a terrorist a courtesy of understanding their motivation or point of view or grow my mindfulness. Murder is evil, terrorists are evil - is there more to understand in anyway other than purely academic?
One is naive to believe understanding the human condition of a murderer by getting to know their family or understanding them pre-radicalized will bring change or make an impact or stop the next one. No offense but in my opinion this is philosophical gibberish.