The obvious way to reach the goal of minimize civilian casualities is to abstain from risky strikes and use smaller yield weapons.

The us military wants technology that justifies them not making more conservative choices, and I don’t see any moral justification for that. Drones are useful for cheaply eliminating risk to one actor, thus allowing more risky behaviour to the side that has them.

But being a cheap risk mitigator is also all they are, they bring no new strategic capability, as evidenced by how easily their use was ramped up and down, so their main effect, the one that could provide some moral justification, is making war cheaper.