One possible moral distinction: even in WWII, when the precision targeting technology just wasn't there, in some cases, ordinary incendiary bombs could be reasonably directed toward enemy troops or assets. You can see this in the early period of the War in Europe, when the US Army Air Corps did daytime bombings focusing on Nazi military assets. This was in contrast to the RAF, which did nighttime carpet bombings of whole cities, city block by city block.
Even if they predictably caused a whole lot of collateral civilian damage, the USAAC was justified in using incendiary bombs targeted "as exactly as they could" ---these bombings, though devstating, were not targeting the civilian per se.
I don't know whether the bombings of e.g. Tokyo were intended to slaughter and incinerate civilians, or if they were focused on military assets but (collaterally) resulted in horrific city-consuming firestorms. If they were solely intended to destroy military assets, they were justified. If they were not --- if they were intentionally focused on civilians, or deliberately indiscriminate --- they were the moral equivalent of Auschwitz, the London Blitz, or Planned Parenthood.
“No. If the intent was the indiscriminate killing of the innocent, then the means is just a technical detail. It doesn’t matter whether you kill them with incendiaries or nukes, with a bomb, abortion or a baseball bat.”
The “intent” was to strike military targets in both Hiroshima and Nagasaki, as well as destroying the Japanese will to resist. The civilian deaths were “collateral damage”. In terms of intent, the firebombings of Tokyo, Dresden and other cities were less defensible. Note that even today, there is unavoidable collateral damage in military conflict. Are our soldiers “murderers”? I think not.
(As an aside, war in biblical times was typically in many ways much more barbaric than today.)
Personally, I think the decision to drop the bombs was a good one, for reasons given many other places in this thread.
You might also want to reflect on the fact that nuclear weapons, bolstered by the effects of their actual usage, have probably saved countless millions of lives since WWII by preventing another world war.
Thank you.