How would you put it better? I mean, they consider using suicide car bombers and anti-population air strikes as legitimate war tactics! Do you know a single civilized-world country that would accept those?
The USA hasn't really done direct civilian targeting with bombing since Vietnam and Cambodia. To the best of my recollection. But that could be because the USA has unilateral power and doesn't need to engage in that. The plan was certainly to nuke all the major cities in Russia until fairly recently. Plenty of generals called for pre-emptive nuclear strikes.
But you know, Hiroshima, Nagasaki, Dresden. etc etc. They fit what you said exactly:
- anti-population air strikes
- legitimate war tactics
- a single civilized-world country that would accept those
Plenty of Americans continue to justify those as legitimate war tactics even today, even though all of those were designed to shock the enemy by killing large numbers of civilians (those cities did not contain military targets).
Oddly, in spite of the above, the most common justification is that all of these three
did contain legitimate military targets.
Hiroshima: Headquarters for the Second General Army (responsible for the defense of southern Japan) and 59th Army. Major military manufacturing complex for military armaments, though untouched because few airplanes were manufactured here. Major port for shipping, hence why significant stockpiles of armaments had been emplaced.
Nagasaki: One of the largest sea ports of southern Japan. While lacking in major military emplacements apart from a major POW camp, what it hosted was several major shipyards key to the IJN, an armaments plant, and a combined steel/armaments plant which combined accounted for 90% of the city's industrial output.
Kokura (oft-ignored in these lists; Nagasaki had always been a fall-back option for when sightings couldn't be made on this city): Home of one of the, if not the largest single munitions plant in Japan, if I recall properly. More importantly, however, the target for the Kokura run (obscured by smoke) was the nearby Yawata Steel Works, which in itself produced a quarter of the entire rolled steel yield of Japan.
Dresden: Reputedly requested as a target by the Soviets in order to prevent withdrawing German forces from using it as a regrouping point for a counterattack during the Vistula-Oder offensive, but more practically (and irrespective of these claims, which I suspect of being rather dubious) playing into British concerns that the Germans might hold on into late in the year if they could stop the Soviets from taking Silesia. A transportation nexus for the area and the location of an estimated over-100 medium-to-large munitions factories, including poison gas, anti-aircraft, and field guns.
Let's be honest, in the decision-making process, the people in charge were actually more likely to reject a valid military target for cultural reasons than the converse; Kyoto, famously, was scrubbed by Truman personally for this reason ("Even if the Japs are savages, ruthless, merciless and fanatic, we as the leader of the world for the common welfare cannot drop that terrible bomb on the old capital [Kyoto] or the new [Tokyo]. [Stimson] and I are in accord. The target will be a purely military one."). Its elimination on cultural grounds was actually what paved the way for Nagasaki to be added to the list. Nagasaki, had almost anything gone differently, would not have been nuked: if Kyoto had not been cut for cultural and historical significance, if Bockscar had not had a faulty fuel pump, if the observer craft had not been half an hour late (forcing Bockscar to burn fuel circling), if Kokura had not been obscured by smoke and clouds, or if there hadn't been a pure last-second break in the heavy cloud cover at Nagasaki.
Regarding Dresden, the more effective arguments against it were not that it was not at all a military target, but rather that its military value was not the primary reason that it was attacked; the suburban areas where manufacturing was concentrated went largely untouched, key military targets to the north were ignored, and while the devastation of Dresden did prevent effective communications through the city, the scale seemed to go far beyond anything necessary for those grounds. Nukes, by contrast, were not entirely clear in their long-term effects or the sheer scale. Through the 40s and early 50s, most military planners considered them very large, very efficient bombs, and nothing more. Much of the modern revulsion against them simply did not exist for lack of experience and knowledge at the time.