But after the invention of the atomic bomb, numerical superiority lost its critical importance.
Even the first atomic bomb Moser—which failed in development—had a kill radius of about 700 meters, and roughly 2 to 3 square kilometers of man-made buildings would face significant damage.
That was just a test bomb with only one kilogram of uranium-235, and with a utilization rate of uranium 235 as low as 1.2%.
The "Little Boy" dropped by the United States on Hiroshima was loaded with a full 64 kilograms of uranium-235, expected to produce an explosive force equivalent to 15,000 tons of TNT.
As long as air superiority could be achieved, such a nuclear bomb would be a massive strike against both the enemy's vital facilities and ground forces.
However, the use of atomic bombs also needed to consider whether it would provoke hatred and animosity from the countries bombarded.