These USA didn’t directly target civilians. Firebomb targets were military and industrial. There’s a difference between collateral and direct targets.
You are wrong. Dresden was purposely set out for total destruction from Bomber Harris. And the USA fully participated in that air raid that went on for 2 or 3 day.
And many cities in Japan were set ablaze. Here’s an excerpt from history.com
“The cluster bombing of the downtown Tokyo suburb of Shitamachi had been approved only a few hours earlier. Shitamachi was composed of roughly 750,000 people living in cramped quarters in wooden-frame buildings. Setting ablaze this “paper city” was a kind of experiment in the effects of firebombing; it would also destroy the light industries, called “shadow factories,” that produced prefabricated war materials destined for Japanese aircraft factories.”