"Officials have stopped short of calling it an act of terrorism, presumably because we don’t know the motive of whoever perpetrated the act" There was another one elsewhere [Washington state [1]] and they found out the perps did it to facilitate knocking over some business of some sort. So, just because it quacks like a duck does not mean it either walks like a duck nor end ends up being a duck. There have also been…
For reference, Greenwood & Crahan's indictment: https://www.justice.gov/media/1266956/dl?inline