This skit where Donald Trump is interviewing himself was a very clever idea of Jimmy Fallon's. He got to feed Trump's ego and poke fun at him at the same time.
Notice that throughout much of this interview, Trumps hand-arm configuration is the classic steeple. Note also that Jimmy Fallon never mirrors this - the most he does (at 0:28 and again during 5:17 - 5:20) is a partial classic steeple with only his index fingers and middle fingers touching. It's quite possible that this is due, at least in part, to his recovering injury of left ring-finger.
The classic steeple (as opposed to the basketball steeple, partial steeple, one-handed steeple, etc.) is a highly alpha body language gesture - indeed it's even hyper-alpha. In very short moments (a second or two at most) it can send signals of confidence and assertiveness - and therefore must be used in small doses, essentially choreographed. Yet most of those who use the classic steeple (and other alpha body language), end up over-using it - thus it backfires - transmitting condescending and patronizing emotions. One thing often realized is over-use of alpha behaviors is very polarizing. Those who like you will like you more - yet people who don't like you or whom are on-the-fence will be driven further away. The person engaging in such nonverbal behavior will often feel more powerful and vindicated (much like yelling does [in the moment] during an argument) - but the projected arrogance is extremely off-putting and damaging on the receiving end.
Notice how Fallon's abbreviated, partial classic steeple feels a good bit less patronizing vs. Trump's full classic steeple.
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