I think the media has a lot to do with these killings with all the coverage of police brutality against minorities. You add the coverage on the mass shootings over the past few years and it creates a cocktail for the crazies to be drunk with mentally. Shootings in churches and "religious" places aren't new. There are terrorist acts done quite frequently in Mosques in other countries. Just like others stated, What gets me is the reaction that these places are "safe" from terror. There are tons of movies that place violence in churches. One of which recently, Kingsman: the secret service. The movie had one of the MOST violent scenes in a racist church which features a British hero.
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