Air superiority, then air supremecy, then naval supremecy, then land war.
At that point the land forces can be supported by naval and air forces unfettered by any opposition.
Military forces and targets are all that should be attacked, as there is nothing to gain militarily by indiscriminate attacks on civilians.
All of this is our present day doctrine.
In a time where our stand-off weapons possess the accuracy and precision required to do the job. The 'indiscriminate' attacks on civilians was a result of civilians co-locating with military targets within the CEP of the weapons available at the time. Mass bomber raids were used because cities were the only thing that could be reliably hit. The weapons required a large target area to have effects.
There is plenty to be gained militarily by destroying the factories and workers that produce the bombs,bullets,fuel and equipment,even the food, of the enemy.
Old time navies intercepted and captured or sunk commercial shipping to cripple the enemy economy.Aircraft just extended the reach.
If we must fight then we should fight to win.