Because violating copyright is not the same as stealing (at all), or stealing a car (which the copyright industry loves to say it is), or detonating explosives in a mosque (which this article conflates it with).
Radical terrorism is an enormous red herring simply because only a very small percentage of the total population will engage in it, they are easy to identify (Israel has been doing it successfully for years), and regulating their _computer_ use will not make or break their aims.
Therefore, we must logically conclude that the article is really about copyright, and not terrorism.
If I may make an even stronger statement, to hopefully spark an interesting conversation:
I have hope. Spontaneous cooperation between equal peers which unintentionally upsets the status quo and becomes the inflection point for political change for the good has been a longstanding tradition.
The requirements are:
1. Equal peers who abide basic human rights such that cooperation is possible.
2. Pent-up desire for political change for the good which needs a catalyst/release valve.
3. Critical mass of willing participants who, if they discover new status quo, can immediately grasp its significance. (a.k.a. The Innovator's Dilemma)
4. Method of communication which enables #3 to cause the political change.