On "eugenics" - what if the most significant factor in differences in intelligence is social rather than genetic? What if intensive parenting practices like near-constant eye contact and talking to infants and toddlers, long hours of reading to preschoolers, and a steady stream of enriching extra-curricular activites for schoolage kids accounts for larger intelligence gains over the generations than could be explained by genetic variations alone?
Then we need to encourage people to be better parents.
Regardless of whether the effect is cultural or genetic, smart people have smart kids. Although I'd like it to be cultural, I tend to think the latter. In either case, we want to encourage smart people to reproduce.