Dresden was considered a railhead for re-inforcing the Ostheer.
Bomber Harris had his motives ~ and he kept them to himself.
Some analysts suggest bombing Dresden was a total waste of resources that could have been better used in taking out some of the railroads that led to the Nazi death camps.
Guess a lot of this stuff depends on your concerns.
Frankly, if we'd simply held off D-Day for a year, we'd had atom bombs and there'd been no need for an invasion. I have several relatives who'd have lived quite long lives without D-Day.