I certainly accept the vulnerability of people in groups to powerful orators and to peer pressure to behave in certain ways, including accepting certain ideas as "right", Donuel. I have a number of reservations about calling it hypnosis, though. Three of these are
(a) giving something a name fools some people into thinking we know what it is. (I know you are a Richard Feynman fan, so see his discussion with his father on naming a bird species.)
(b) there are a least two "mind states": one is passively accepting what 'your side' says, the other is using every mental faculty you have to defend it from attack. I am not sure a single term adequately covers both.
(c) in so far as people find 'hypnosis' a useful metaphor, all well and good. But I think other metaphors will work better for other people.