Thanks for a new (to me) thought.

This article brought to my mind how, prior to WWI, there was the idea in Europe of 'civilized' warfare. At the same time, though, the concept of 'total war' had been advancing along with the realization that a nation's economic strength translated into military strength, and the scales of conflicts had increased along with the scales of geopolitical units. It is the case that in WWI there was some shelling of cities, but the ability to strike cities depended on having armies in very close proximity to them, which was almost completely prevented by the mutually unbreakable defensive lines that formed. At that time airplanes could do way less damage that artillery could. Also, WWI was only nascently a war of ideology--involving the ideology of nationalism--but WWII was wholly a war of clashing ideologies. Like religious conflicts, that undoubtedly redoubled the viciousness of it--on a global scale.