U.S. Secretary of State John Kerry is shown here reacting during the "Chairman's Debate" at the 51st Munich Security Conference at the 'Bayerischer Hof' hotel in Munich, Germany on 8 February 2015.
John Kerry's mouth expression is that of fear ("Mouth of Fear"). No video of this moment is currently available - so it's not possible to put this in full context (although there are some hints - see below). This very probably was a very brief expression - possibly a microexpression. Notice how the corners of his mouth are pulled laterally and downwards - more so on his left. Also in this context, the wrinkling of his chin signifies that his neck muscles (his neck is minimally visible) are at least mild-moderately tightened in a concomitant "Neck of Fear". The Secretary's eye lids are also opened slightly wider than baseline along with a contraction of the entire width of his forehead. His hands are held out in front of his body in a protective configuration.
John Kerry's body language at this moment demonstrates a cluster of fear.
What else do you see in this photo that is not described here? You should be able to see a hint of another emotion - thus some emotional dissonance - which would give you a larger context for this moment.
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