how many lives an action saves is less important than the emotional connotations of the act which takes the lives. take micronutrient dispersal programs vs terrorism. malnutrition kills orders of magnitude more people and yet far more money is spent on terrorist prevention (well, mostly terrorist prevention signaling, but that's another topic). This is because fighting terrorism is more exciting than fighting scurvy. The order of magnitude difference in impact is ignored when evaluating which thing to spend money on. This makes choosing terrorism easier as saving 100 people from terrorism is much better for public relations than saving 100 random kids with goiters.
we must adapt ourselves to live here, not somewhere else.
I try to explain this when I get called a racist for not wanting to go to a poor/predominantly black and latino neighborhood. I have a high preference for a world in which race doesn't make a bit of difference. However today, in this world I am 2 orders of magnitude more likely to have a crime perpetrated against me in said neighborhood.
I also bring this up when people respond to my ideas with unlikely sinking ship/rescue raft ethical scenarios. There are enough regular problems that need solving. As the world becomes more gentle we can start putting more effort into the edge cases.
And again with global warming. I'd love to live in a world in which a .3% change in radiation absorption was our most pressing concern. However in this world we could save many more lives and species by refocusing our money and efforts.