A state of the union address in the sixth year of a presidency is inevitably buffeted by the crosswinds of time. The president has been in power long enough that their record has already eclipsed their potential. But they have too long remaining to start openly making an appeal for their place in history.

On Tuesday 7 January Darrin Manning, 16, emerged from the Philadelphia subway with his high school basketball team-mates on their way to a game. With the region in the grip of the polar vortex it was viciously cold – so harsh their principal had given them hats, gloves and scarves to wear. The youngsters say they saw a police officer "staring them down" and Manning says one of them "may have said something smart". The police say they saw a dozen young men running in "ski masks". The police gave chase; the young men ran. Manning stopped running thinking it implied guilt. "I didn't do anything wrong." He was first tackled to the ground by several police and then frisked by a female officer with such ferocity that he ended up in hospital with a ruptured testicle.