One could argue that the US has put a great deal of time, effort and R&D into saving civilian lives, through the drone program itself. The alternative to the drone program is a traditional military occupation, which would presumably have a much greater death toll, I don't have access to the research.
Or, of course, simply not fighting the war at all. But it doesn't seem like that option is available.
Civilian lives? A more persuasive argument is that primarily it's a tool to be used when popular opinion at home would simply not allow another full-scale military adventure like Iraq or Afghanistan. Secondary consideration is saving US military lives. Foreign civilian lives is by far not the primary concern.
Drone strike target to civilian ratio is over 90%. The reason, and the only reason that the US went to drones is to reduce the cost of operations, with the additional benefit of reducing danger to US personnel.
https://www.theguardian.com/us-news/2014/nov/24/-sp-us-drone...
Or, of course, simply not fighting the war at all. But it doesn't seem like that option is available.