Obeying Allah, prophet al-Khidr murdered a boy whom he feared would later oppress his parents with "transgression & disbelief" (Quran 18:74-18:80). Why did Allah have this boy killed, instead of killing every boy who grew up to become an evil tyrant?

Eliminating children before they become evil, homicidal dictators was NOT a priority to Allah

"Compassionate and Merciful" Allah was most concerned about the parents of al-Khidr's victim, but where was Allah's concern for the parents of all the victims of mass murderers?
Would the world have been a better place had Hitler and Stalin been murdered by Allah before they became adults?
Is the alleged oppression of 2 parents arising from the "rebellion & disbelief" truly a greater calamity than the deaths of thousands due to mass murderers?

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