That 'military objectives only" thing was tried in WW2, but found wanting. In bombing against both Germany and Japan, it was found that destroying civilians' homes was far more effective.

Read up on Curtis Le May's methods in Germany, Japan, and then later in North Korea. He was a great proponent of fire-bombing large areas in the centre of cities.

https://en.wikipedia.org/wiki/Bombing_of_Tokyo

One fire-bombing raid killed as many people in Tokyo as were killed a few months later in Hiroshima's atom-bombing.