Steven Pinker's opinion on how attacks like this one fit with the supposed general decline in violence:
http://news.harvard.edu/gazette/stor...-yes-actually/Certain categories of violence could continue to see statistical declines, Pinker said, including homicide, domestic violence, and rape. But others, notably the use of “cheap, low-depth, high-publicity violence such as terrorism and rampage shootings,” may hold to current levels far into the future.
Reflecting on overall historical trends, Pinker said, “Violence reduction might be like other types of technological progress — that is, not linear and not exorable, but highly likely over the long run.”
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