It’s only eleven minutes long. Professor Martha Crenshaw looks at the “macro” (e.g. poverty) and “micro” (e.g. psychology) explanations, pointing out their limitations, and then addresses “meso” explanations — the ones that I have often addressed in various posts on Vridar.
From http://www.heatherhastie.com/what-is-terrorism/ — where one can find two more related videos.