Snape bullied everyone except for his Slytherin students.

The argument

The case against Severus Snape as a hero points to the way he treated those in his power, arguing that genuine heroism is incompatible with the casual cruelty he showed as a teacher. Throughout the series Snape bullies his students — belittling them, mocking their failures, exploiting their fears and dispensing punishment with evident relish — while reserving favour almost exclusively for the pupils of his own house, Slytherin. His treatment of Neville Longbottom is so frightening that the boy's greatest fear, when asked to confront it, takes the form of Snape himself; his contempt for Harry and Hermione is petty and persistent. A person in a position of trust over children, this argument holds, who systematically abuses that power, reveals a character at odds with heroism. The objection is that bravery in one arena does not excuse cruelty in another. Whatever Snape's later services against Voldemort, they do not undo the fact that, day after day, he chose to torment the vulnerable young people placed in his care, including some who had done nothing to deserve it. Heroism, on this view, is not only about grand acts of courage but about how one treats those who cannot fight back, and by that measure Snape repeatedly failed. Cruelty exercised over children is a moral failing that sits ill with the title of hero. A man may do some good and still not be a hero if his conduct toward the powerless is habitually cruel. Snape's bullying was not a single lapse but a sustained pattern, partial and vindictive. Because Snape bullied everyone except his own Slytherin students, abusing his authority over children, this argument holds, Severus Snape was not a hero.

Premises

Counter-arguments

Defenders reply that heroism turns on decisive moral action under mortal risk, and that Snape's years as a double agent — and his death in that service — outweigh an unpleasant classroom manner. They argue his harshness, though real, is partly explained by the strain of maintaining a lethal cover and by his own abusive history, and that cruelty as a teacher is a serious character flaw but a different question from whether his conduct in the war was heroic. A person can be both a poor teacher and a hero; unkindness to pupils does not erase courageous, self-sacrificing service that proved vital to defeating Voldemort.

Rejecting the premises

[Rejecting P2] That Snape frightened pupils like Neville shows he was a cruel teacher, but classroom conduct is a separate question from whether his wartime actions were heroic. [Rejecting P3] Heroism can coexist with serious personal flaws; a hero is not required to be kind, so bullying does not by itself cancel courageous, self-sacrificing service.