If one side is evil (you know which one im talking about), if the other one is doing the same in a bigger scale, that justifyes it all?
Nope. There were horrible deeds on both sides. That German mother in Dresden was just as innocent as the one in London or Coventry. The sin just remains a sin. This should never happen again.
The soldiers were heroes on both sides: they got orders, they did it, sometimes they paid with their lives. Respect and salute to them. But not to those who ordered them to do those deeds. On both sides!
Im not going to argue this but I'll sat that in no other time in history was the balance of right and wrong so clear as in WW2. The perfect storm that put the Nazis in power, and the fact that "most" Germans werent Nazis, and if asked, probably preferred peace doesnt matter. This isnt from a moral perspective but from a practical one. The simple fact is the German Govt. started a war of aggression and then followed an official policy of enslavement and genocide on a scale never before seen in history. Theres nothing to "moralize" here cause the facts are clear and does anybody truly have any illusions about what kind of world we'd be living in had the Axis won?
Most of all Germany. A modern Industrialized state made even more powerful by its slave labor force and resources stolen from occupied countries. There was no recourse but to use the same tactics Germany herself first used, and then pursued, and that was the bombing of cities. Kill the worker and burn the factory and you have less output. Whether it worked or not you cant say it didnt force Germany to pour huge resources to stop the bombers. Resources they'd have preferred to use elsewhere.
Ive never been to Japan but if you go to Germany today its almost impossable to believe this country started such a destructive war. And that "most" of its citizens backed Hitler as long as they were winning. But they did and none of this is an Intellectual exercise ; It really did happen. The Brits and Bomber Command did what they had to do to stop them, its as simple as that.
Theres never been even close to such a destructive war since. Even with nukes all over the world. Maybe humanity finally learned its lesson. Or maybe saving the dream of Democracy and freedom prevented it.

To the crews of Bomber Command.