Just one thought to add on the liberal guilt question, beyond what Ross Douthat and Jonah have well said.

On the matter of eugenics, which Jonah mentioned, I think there’s much more at stake than a question of guilt. To me, the relevance of progressive support for eugenics a century ago has less to do with a need to atone for the past, and more with the fact that some progressives are today increasingly open to a new kind of eugenics, so what the progressives of the past had to say about the old kind has some crucial bearing on what contemporary progressives say about modern-day liberal eugenics. The old and the new eugenics are different — today’s form is not obsessed with racial purity and does not employ government coercion, and these are very important differences — but they are also deeply linked because they both rely on a denial of human equality (which is otherwise so important to the left) to reject the weakest and most vulnerable among us. That, to me, is the most important reason to raise the progressive eugenics of the past, as I argue here. It is a means to understanding what might lay behind a growing contemporary problem, more than a means of holding today’s left accountable for sins of the past.