Check out this line from the article:
Just as an epidemic can be averted by an effective vaccine, violence can be prevented if society is prepared to learn from history — if the US government creates more jobs for graduates, say, or acts decisively to reduce inequality.
Bwahahaha! The GOVERNMENT cannot mandate more jobs. If so, then Obama would be a hero with no unemployment by now. Reduces inequality? Defined as and by who? Oh, how noble, comrade! Raise your fist in a power salute!
I like your last question because it points to the major flaw in all liberal thinking: definitions. They just make things up and let their imaginations fill in the facts. Try to pin them down on the meaning of “sustainable” or “hate” and they flutter away in confusion.