Ideas stem from individuals that express it via speech, or through readings or through media presentations. With the manchester attack and the london bridge attacks, it seems that people, specifically those with psychological illnesses untreated, have this tendency to try out new ways of hurting others. This has nothing to do with "jihadism" or Islam. The Paris attacks presented these individuals with new ways of killing others and destroying humanity. The media shows these individuals with mental illnesses and ourselves, pictures and videos of these events which just leads to a cascade of negative events down the road. I say this because with the uprising of technology now through news channels, Instagram and other media platforms, people are really prone to grabbing ideas from other people that have accomplished that specific idea previously. Then, you ask, what is the solution? How would these terror attacks or killings of humanity stop? Well, the media, as it is, already decides what is presented and what isn't.
That is, exciting news that catches peoples' attention is brought forward, while the less exciting news or private information is hidden. So, since this is already implicated, why present news that will grab peoples attention all over the world to duplicate these bad actions? Even some exciting news should be left out of the media because people of the extremist ends will try out these new ways and the events will continue. Once the media protrays this image of Islam and terror with these methods of killing, such as running people over in a van or truck (Paris, Germany, London, etc), those individuals with extreme psychological illnesses will exacerbate the problem and actually create a stream of events down the road since they saw it on television or heard it on the radio. We can see this being evident when the Paris attacks happened with the truck running tons of people over and the following event occured in Germany with similiar techniques of killing, and now, London Bridge, England.

The groups that control the media should think twice about showing certain events because, yes most indivduals that are free from mental illness and free from superstition/Jihad will think it is wrong, but those few individuals watching that aren't will decide to implement those same actions shown on television.
This is my overall view of it and it seems to be evident with many social issues aside from Islam and terrorism, such as the fighting/tension between African American individuals and the policing units of the United states.
The power of what media presents us is never a joke. News channels, Instagram, Twitter, and Facebook, as well as any other media platforms, really have an impact on the normal individual free of health complications or extremist views, as well as more so on the person who has extremist views.