I don't think anybody is denying the existence of evil before the internet. But that truism proofs nothing except that the internet is not a necessary condition

I don't think anybody is denying the existence of evil before the internet. But that truism proofs nothing except that the internet is not a necessary condition for every single extremist to be radicalised. As long as you have cows you will have hamburgers, indeed! But the availability of cheese can nonetheless change the frequency of hamburger, as well as their individual qualities. By using the internet for radicalisations (a fact almost universal along recent attackers in the US) these people have quite clearly demonstrated their believe in the effectiveness of the net for their cause. We usually rely on local, individual decision-making to optimise everything, and I don't see a reason why these people (despite their obvious moral failures) should be an exception from this dramatically successful concept. This evidence becomes even stronger considering we're looking at the subset of "successful" attackers. It also feels intuitively correct to consider the net a tool that helps such movement. That's just because by default, it seems to help almost every endeavour in some way or other. Radicalising a young white nationalist isn't much different from getting them to vote or buy a specific brand of sneakers. If anything, the specific challenges of illegal activities of a small, geographically dispersed set of loners seem to be a unique fit to this particular tool.