This video segment of President Obama on the David Letterman Show is just 1:20 in duration - however there are several interesting body language tells. Here are two of them:
When David Letterman asks the President about his interpretation of Mitt Romney's now infamous "47% remark" - note how Obama remains leaning back in his chair with his legs crossed (doing his best Matt Lauer). While the President certainly wants to relax - he should take care NOT to come off disengaged. He would have been well-advised to plant both feet on the floor, a bit wider apart than his shoulders - and leaned forward as he answered David's question. His backward-leaning, legs-crossed configuration gives the impression of aloofness and does not build rapport or engage the electorate.
At the 1:05 mark - just a fraction of a second after he says, "hard working" and just before he says "family" - the President displays a classic microexpression of contempt (play these few seconds several times, it may be difficult to see initially). This lasted less than 0.1 second, yet it is a highly reliable nonverbal signal of Barack Obama's emotional tone - at that moment.
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