Close, but no cigar. McVeigh was a honky, but he spent time with a West German (former RAF) who spent a good part of the 80s in the Bekaa Valley. Said German was currently (1990s) a double-agent, working with the FBI and ATF as an agent provocateur, supposedly assisiting in ferreting out doemstic terror groups. Of course FBI/ATF lost track of him...oops. And, of course, Elohim City was well known since the late 70s, but that would not have been a sufficiently spectacular bust. (No, I'm not "that kind" of conspiracist, but it is well documented that the DOJ thought they could be clever, and had aims to bring favorable press to the Administration- and ignored the Law of Unintended Consequences.)
Some people simply like to kill. There is no "recruitment strategy", no particular paradigm that may be identified, other than generalized sociopathy. This is the reason the Provos, Baader-Meinhoff, Hezbollah, the Red Army Faction, et al, all spent much of the 80s and early 90s sending their homeboys to the Bekka Valley for summer camp.
Now, even conceding that, it is undeniable that certain political and religious models are clearly more prone to fostering racial hatred.
Behring Breivik (unfortunately for the mass media) is not a Christian Fundamentalist Terrorist, nor a "Whit Al-Queda operative". He is a neo-Nazi, and the enlightened Socialists in Norway are now stuck pondering how best to keep him imprisoned for life (legally) and without making him a martyr- instead of simply popping his grape.
I have no love for either Socialists or Fascists, but if one undrstands how these theo-philosophical movements interact and generate emotion, it is much easier to see how homogeneous societies may not be in our best interests.
Stating that violent actors cannot be identified, or stopped in situ, is patently false, but is an excellent tool for expanding and reinforcing social control and power.