indeed, the japanese cities were chosen due to their geography (in order to focus the explosion, ensuring greater destruction/number of dead civilians
If that were the case (which it isn't), then Nagasaki with it's "lumpy" topography would never have been on the list.
Both both Hiroshima and Nagasaki were chosen because they were military targets.
Look up Hiroshima and the reasons for it being chosen.
Plus, you forgot to address the part about the wooden constructions (generally, you seem to willfully ignore bits of history - they not fitting your attempts to morally bleach events).
BTW, labeling something 'military target' (pretty arbitrarily, in this case) does not give one a moral free pass; indeed, it's only a particularly poor attempt at justifying whatever.