A.N.: Whenever I come across a fic that paints Dumbledore as a villain on the same level as Voldemort, there are a few things that come to mind:
1- Rowling did too good a job of portraying the man as a wise old man who had powers that were almost on the level of omnipotence, because people seem to think he orchestrated all the events from book one to book seven with the precision of a clockmaker, with comments such as: he raised Harry like a pig for slaughter. You can't make that assertion without saying that Dumbledore had as much knowledge as J.K. Rowling herself.
2- And that one is something that the costume designs in the movies really proved for me as soon as the 1st Harry Potter movie came out: people don't seem to grasp the extent of the segregation between the Wizarding and muggle world. I honestly think that people (especially those who think Dumbledore was as malicious as Voldemort) elevate Dumbledore and his abilities much higher than the reality. A little like the majority of the Wizarding community did.
This author's note will be a little lengthy, but please bare with me.
In this longer-than-usual note, I just want to address the lighter points. The littles things Dumbledore is often criticized for are things like: leaving Harry on a doorstep. Who would do such a thing in the 80s? Well, the practice of leaving babies on doorsteps hadn't been that old even in our world. All the way into the the 60s, even much later in some places, it was common for babies to be left on the doorstep of fire stations, churches or orphanages, without any consequences to the parents (It is to this day in some places acceptable, in other places a gray area). Now, let's put that in the context of a society who still has a lot of it's ideologies stuck at least a century in the past. Dumbledore is the greatest wizard of his age, and just like the most progressive man in 1802, we cannot hold him to the standard of someone who is somewhat progressive in our current culture and time. He may be the smartest wizard in Europe, maybe even the whole world, but that doesn't include the muggle world and their knowledge and ideologies. He is still a product of the culture he spent his entire life in.
There is no indication that he frequents muggles on a regular enough basis for their culture to have influenced him beyond a few broad points. Same goes with the abuse he put Harry through. It wasn't too long ago the majority of people thought a good strong beating built character in a child... In fact there are still people who think that. People who clearly have over the top aggressive and violent personalities who say:"My father beat me and I turned out fine!"
So it's not shocking for someone who was raised in a stagnant community that cultivates a mentality decades behind the rest of the world, to think the same. It used to be believed (not that long ago) that the parent(s) or (should the parent(s) die) the gardian of a child had the right to raise that child however they saw fit without anyone having a word to say about it.
Wizards have sheltered themselves from all the big scientific discoveries, and immerse and isolate muggleborns so completely into their world, during important formative years, that they end up leaving everything muggle behind, integrating the Wizarding world completely with very little contact with the muggle world. The same type of culture "erasing" has been done in our world.
With magic, the Wizarding community obviously has no use for the technological advances that science brings to the muggle world, which is why they don't have math and science in Wizarding schools, but without even knowing it, they end up falling far behind in the understanding of the natural world, and stay stuck with archaic ideas like the ones they have about blood and lineage.
Dumbledore is an incredibly knowledgeable and powerful wizard, and he knows more about magic than any other wizard we encounter in the series, but that's where his knowledge stops. He simply cannot be held to even the same level as a university student when it comes to certain things, and therefore should only be compared to his peers.
Professor Albus Dumbledore in context
Imagine you're a very old man, who is extremely well respected in your community. Except, the thing you're respected for isn't really a point of pride for you. It's something that brings you pain and sorrow on many levels. You've made many mistakes and you've had many regrets.
Most of them, of course, you've learned and grown from, but it doesn't dull the pain from the memories. You've changed your stance on things a few times over the course of your life. Some as you grew into an adult and gained experience and perspective. Some as the result of painful consequences to actions you posed. And some yet as you became old enough to recognize the source of some problems.
You defeated a powerful dark wizard in your youth (well, youth is relative isn't it?), something that, when no one else had the power to do, you didn't even know if you had the heart to carry out. Gellert Grindelwald had been your dearest friend, and so much more in the depth of your heart. You had admired him, loved him, shared so many things with him; opinions, passions, adventures ...
But the fall from grace was a long, dizzying one. It had birthed wounds that would never heal. And as you came face to face with your mistakes, as you came to term with your past and accepted the harsh lesson life had laid out, the Wizarding world celebrated you.
They had put you on a pedestal as high as Merlin himself. They offered you countless titles and honors, even requesting you become Minister of Magic. But you thought the best way to insure people learn from your mistakes was to become a teacher. Influence young minds to steer away from the path you once pursued.
Perhaps it was the wrong decision, or the challenge had been too great, because the mistakes were repeated nonetheless. A new war surfaced, fueled by an environment you once believed flawless. You tried to prevent it, you tried to contain it, but in the end, change comes too slowly, comfort takes precedence over wellbeing and the horror settles before we can notice.
So many deaths. So much suffering.
You had already seen too much of it, yet there it was again. And once more, the world looked to you to save them. As if it were that simple, a single saviour to fix so many problems that ran so deep within the entire culture. How hard you'd wish they'd find another saviour, another wizard to put their hopes in.
And it was true what they said about wishes. You should be careful, for they might come to pass. And so it did. A prophecy, a double murder... An orphaned boy. If only you had all the answers. If only you were as clever as they all said. If only this was truly over. You were so tired, so old. You had seen so much, done so much, caused so much. If only you could fix everything.
You could always try.
Try to fix everything, try to save everyone, try to be as clever as they said you were. Save everyone. Their lives, their souls... Their future.
You made plans. Searched for clues and answers. You made discoveries and hope began to swell in your heart. You could be as clever as they said. You could fix everything, save the future and stop history from repeating a third time.
But life has a funny way of getting in the way of your plans. A group of children much too clever and resourceful, with a knack for finding trouble. A ghost from the past threatening everything you hold dear in this world. A traitor becomes an ally and a dead man resurfaces to resurrect another before you can even catch your breath, let alone devise a new, faster plan. You now have less time than you counted on.
And you find yourself dragged under the surface by incompetence and corruption and pure malice. Options become limited and decisions become harder. You improvise, you get creative, you hope for the best. You try to protect those who don't want to be protected. You see yourself in a child who wants to save everyone and fix everything, but doesn't want to be anyone's saviour...
And you see so much of yourself that you forget to see a child.
A child who is no longer a child, because he can no longer be one. He is a saviour. And he doesn't want to be protected, but you'll keep trying.
But life has a funny way of getting in the way of your plans. Maybe you forgot how tired you were. Maybe you forgot how much you had seen. Maybe you thought you'd live to be as old as your old neighbor, however, you now have less time than you counted on, less time than what you need.
Not enough time to fix everything, not enough time to save everyone.
Options become limited, decisions become harder and time keeps on getting shorter.
No more options, no more chances... No more time.