The word is useless for describing violent acts in a meaningful way. It can mean making children traumatized with bombs, or making HOA members afraid their property value will decrease with graffiti, vastly different actions and outcomes.
No one who wants to be taken seriously should use the word “terrorist” in a descriptive context. It is not a meaningful word, it’s a noise people make when the word they actually mean is socially inappropriate or politically inopportune.