You don't get to start a completely unprovoked and illegal war of aggression, bomb tons of targets with little care, kill 100 schoolchildren, and then say, "But it was a mistake."
The DoW head sees half of his own country’s population as enemies, Islam as an evil religion of hate, and the work he does as striking down the enemies of God. I heavily doubt that this man gives a single thought to children of muslims.
It's a mistake in the sense that if you go and rob a bank while shooting wildly, you only hit the customers "by mistake." That's not an excuse.
The US is bombing both military and civilian targets, by the way. Trump has been very open about this with his talk about "power-plant day." He considers attacking civilian targets to be a legitimate way of pressuring Iran to surrender.
Hegseth deliberately closed the unit that used to ensure it wont happen. The efforts to avoid civilian causaulities were deemed woke, weak and literally unmanly.
And administration repeatedly threatened to destroy civilian targets.
And however much you can say about the current US Administration, I don't think they're prioritizing bombing civilians over military targets.