Here’s a quotation:
“Dress is a kind of language; but when it is rigidly uniform the only emotions which it can express are emotions common to those who wear it. The habit of wearing it focuses the attention of the wearer on emotions of the kind, and at once generates and expresses a permanent ‘set’ or habit of consciously feeling in the corresponding way. Rupert Brooke noticed that Americans ‘walk better than we; more freely with a taking swing and almost with grace. How much of this is due to living in a democracy, and how much to wearing no braces, it is difficult to determine’.
“Dropping a uniform carries with it a curious breach in the emotional habit. The consciousness of sharing uniform dress with a circle of others is thus a consciousness of emotional solidarity with them; and this, on its negative side, takes a form of emotional hostility towards persons outside the circle. To illustrate this from the history of parties and classes is superfluous.”