Trouble is, they didn't get on to those two target-types until much later in the War...Bomber Command didn't go for 'particular targets', preferring to lay waste to many different industries, wearing them down, city by city....But you are correct, they did get onto these 'panacea' targets, there were just an awful lot of other industries that had to be dealt with first, such as aircraft industries so that they could gain Air Superiority over Germany and the Occupied Countries....