Every mental health professional is aware of the phenomenon of "copycat suicides" that occur after a well-publicized suicide--particularly among more impressionable young people. It's hard to imagine, but the idea of going down in a blaze of glory spectacular enough to make the evening news is attractive and romantic to some.
That's why this news is hardly shocking.
In many real-life situations where there is a fear of copycat suicides, the local media will voluntarily suppress any stories that might trigger the copycats. I know this because I have worked with reporters and editors about this very thing. When lives are at stake, the media used to be reasonable and not want to romaticize or overly dramatize these kinds of tragedies. In such cases, the news outlets don't generally want to benefit circulation at the expense of human life - a worthy and honorable position.
Yet, that is exactly what they are doing in this war, whether they admit it to themselves or not.
Perhaps now that there is objective data to show them, it will be possible for them to exercise a little restraint; and even if they report on a particular terrorist attack and give the details of it, they might actually refrain from blatantly showing their admiration for the terrorists and/or editorializing about how hopeless it is to fight against such tactics.