A very disturbingly high percentage of the population would see most folks dead if they saw no personal consequences for it.
I remember in college hearing an prof go on about how GREAT it would be if 40% of the world's population just 'disappeared.'
Because they don't see that as advocating the murder of more than two-and-three-quarters *BILLION* currently-living human beings. "Disappeared" is a so-much-more SANITARY word, without all those nasty, messy connotations...
As long as "someone else" makes it all happen, they don't have to get their own hands dirty, or put forth any effort or suffer any hardship in connection with their convictions and beliefs.
Not to mention that 2.75 billion dead bodies would create a pretty major health issue for the remaining 60%, even IF all those deaths didn't cause a worldwide collapse of what we think of as civilization. Not a whole lot of thought for consequences in that sort of mindset, IMO - which is ironic, given that that's precisely what they're accusing their opponents of suffering from...