Charismatic authority revels in the glamour and irrationality of visual images, just as it revels in emotion, stridency, fear and loathing.

Tea Party: A populist conservative movement known for its uncompromising stance on fiscal issues, its disdain for Mr Obama, and the stridency of its rhetoric.

But within the context of the evening, his stridency was open to a reading of “a passionate nominee wanting to improve things.”