Is that because you can't address it? Because his thesis seems quite reasonable to me. And historically, we certainly know that societies with extreme income inequality are less stable than those with more equality.
Lots of countries with high income inequality do not have a terrorism problem.
When is the last time Brazilians terrorists attacked New York and/or Paris?
https://en.wikipedia.org/wiki/List_of_countries_by_income_eq...
Sure, you can say that inequality may have contributed to the issue, but there are a ton of factors that have resulted in Syria being plunged in Civil War. Pointing to any one as a decisive factor seems like an inevitable simplification. Also, it doesn't really answer the question "Why _now_?". Claiming that something eventually happen is not really predictive if no time frame can be given.
† Or I might be overly optimistic about my own country's stability.
I don't see anywhere in Piketty's theory a place to plug in "Amount of Inequality" and expected number of deaths.
I'd like to see a regression plot at least.
I'm sorry I can't buy this, and I can't genuinely handle this properly so I'll probably stop here before it gets darker.
"What do you actually think is wrong with Piketty's analysis, other than the fact that he has actually published on this topic before?"