Eric Raymond makes a distinction that should be pretty obvious.
A lone wacko is a tragedy but almost never a disaster; a terror network can scale up violence to much greater levels by deploying multiple soldiers, and is far more likely to have expertise in bomb-making, airplane hijackings, and other means that can inflict casualties well above the level of a rampage shooting with personal firearms.
One of his more tendentious claims is that many on the left go out of their way to misclassify these two types, because
the left end of the American political spectrum is heavily invested in the belief that “right-wing terrorism” is prevalent in the U.S. and a greater danger than either left terrorism or Islamism.
From the oppressor-oppressed axis point of view, you want to lean in the direction of treating a lone wacko who attacks a Planned Parenthood facility as a terror soldier, and you want to lean in the direction of treating an Islamist terror soldier who attacks an American military base as a lone wacko.
Raymond’s sensible analysis leads to sensible conclusions.
Rampage killings are a public health problem – police may be the first responders to an incident, but the effective interventions to prevent them them are mainly medical, not criminological.
On the other hand, what terror soldiers do is best thought of as a kind of distributed irregular warfare, intended like all warfare to break the enemy’s will to resist. Criminal enforcement can typically do little or nothing about their networks. Instead, the normal counter to irregular warfare applies; you want to bait them into concentrating so they can be confronted and destroyed by regular forces.
That was the French strategy in what was then Indochina in 1954, when they deliberately set up their base in a valley in order to lure the opposing general into concentrating his forces nearby. The resulting battle and its outcome are historically significant.