Its very easy to criticise the bombing of Dresden, but the issues are far more complex than the armchair historians who weren't even born at the time, and criticise in hindsight, can imagine.
Firstly, you have to appreciate the collective single mindedness of the English people, who fought the war alone, until joined by the Americans in 1942. The attitude of the English was simple, 'We didn't start this war, but were going to bloody well finish it'. Bomber Harris himself said 'They sowed the wind, now they will reap the whirlwind.' The English did not ask for WW2, they had it foisted on them, and so the entire nation considered any means justified the end. It is exactly this reason why, even today, we English feel we have the right to make sure the world never forgets about World War Two.
Secondly, you have appreciate that considerable investment had gone into building a bomber force of 1000 heavy bombers, considering each one took 250,000 man hours to build. For several years, the heavy bomber force was the ONLY weapon the allies had that could strike back at Germany directly. The English people had considerable faith in there armed forces, and weren't going to shed any tears for the enemy.
Why did Harris bomb Dresden? Because he had no choice. To NOT bomb Dresden would have been an admission that he had run out of targets (which he more or less had). He was reduced to bombing whatever was left, since almost all the primary and secondary targets of 1942 had been wiped out by 1944. The English expected Harris to continue to punish Germany, so he couldnt really stop. Had he admitted he had nothing left to bomb, then the RAF might have been scaled back.
But to say it was immoral to bomb Dresden is absurd. The allies did what they collectively felt what they had to do. Remember the Americans also took part in Dresden, and the American people did not feel it was wrong. Harris pointed at that there is no morality in war, war is not the opposite of peace, it is the absence of civilisation, and the absence of civilisation also includes the absence of morality. War is won by the side that is willing to hit hard and go further than any of the opponents, which is basically what the allies did. The Germans blitzed London, so the Allies blitzed Germany. We did to them, what they did to us, but we did it better, harder and more efficiently.
Bomber Harris said at the time 'They call us murderers for bombing Dresden. What would they have called us had we stood by and done nothing about Hitler and his bloody gang?'
And that is exactly the point here.