Looks more like sweat to me. Tears tend to come from the duct near the nose. This is coming from the side of his face, not anywhere near the path a tear would normally follow. But that’s just my humble not-a-medical-expert opinion.
I usually get a tear on the outside of my eye when some moisturizer melts in the heat and drips into my eye, which in turn causes my eye to tear.
Thus obama had a make-up malfunction.