I know that JK really likes Dumbledore, and sees him as a truly good guy, making the hard choices that the rest of us are maybe not so willing to make, for the greater good. And I know that a lot of the fandom thinks that he’s a ruthless, manipulative old coot who needs to have a bit more respect for the lives of those around him. I’m…neutral on this issue. I think that Dumbledore is maybe a little more steely than you would assume on the first go-around, but I also think that he’s truly on the side of good and isn’t blinded by power (ahem, Crouch, Umbridge ) or still being angry at a girl not wanting to sleep with him (Snape).
That being said, I wonder sometimes if JK didn’t give us a hint about the danger behind Dumbledore’s facade. Because while most of the character’s who aren’t Death Eaters love Dumbledore and trust him implicitly (a big clue to the Malfoy’s loyalties comes with Draco’s attitude toward Albus), Hagrid in particular is violently loyal to Dumbledore – literally inflicting bodily harm on folks who dare disrespect Dumbledore in his hearing. Ostensibly, the reasoning for this is that Dumbledore allowed him to stay on as groundskeeper after he was expelled, and hired him on as a teacher despite not having technically finished his education (and by extension giving him a home within a wizarding world that was hostile at best towards his parentage). But if Hagrid has one defining character trait, it’s being drawn to – and defending – creatures that are dangerous and even deadly.
That trait can, of course, be explained by the fact of his heritage and the fact that many witches and wizards considered Hagrid himself to be dangerous because of his mother. But I think that if we pull back the curtain a little bit, it’s a pretty big red flag that the character who is most drawn to dangerous creatures is also most loyal to Dumbledore. JK tells us over and over again that Hagrid is incapable of seeing the danger in any of the creatures he loves – dragons, skrewts, Aragog – despite the dangers being real and clear to anyone but Hagrid. In retrospect, it sort of makes the ruthless and dangerous nature of Dumbledore more obvious – after all, would Hagrid love someone without a dangerous streak?