By BENEDICT CAREY, New York Times, JULY 26, 2016
The horrifying rash of massacres during this violent summer suggests that public, widely covered rampage killings have led to a kind of contagion, prompting a small number of people with strong personal grievances and scant political ideology to mine previous attacks for both methods and potential targets to express their lethal anger and despair.
The Iranian-German who killed nine people at a Munich mall was reportedly obsessed with mass killings, particularly the attack by a Norwegian that killed 77 people in 2011. The Tunisian who killed 84 people at a Bastille Day celebration in Nice, France, also researched previous attacks, including the mass killing in Orlando, Fla. The Orlando gunman had reportedly researched the San Bernardino, Calif., attack.
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