Reading the letter from spite-filled Jewish Lisa, my first reaction was to jeer her, like many of your readers (here and here). How could someone with a caring, leftist background turn so bitter and hateful?
But I try to listen to my inner Buddhist when I can. Instead of condemning, my IB wants to comprehend. So I got to wondering -- why did she turn out this way? What converted her from a leftist Spanish-teacher type to someone who labels life's losers as "vermin"? She must have been through a lot of pain and poverty, possibly a victim of crime.