my speculation on the reasoning behind the day-glo red panstsuit is something like this: hillary and nancy are relatively small people. and because of lingering sexist attitudes, a female presence doesn't command a room in the same way that a man's might. but it's their job to command a room. so some consultant figured out that if the clothing screeches, all eyes are riveted by the pulsing glow. thus what barack can do in a black suit, hilary can only do by looking something like a pylon. let me point out some of the problems with this. one way that obama can actually command a room is by quiet dignity. hard to muster quiet dignity in a fire-engine-red faux-silk pantsuit. and of course, personally, i select my leaders by their taste: when bill used "don't stop thinking about tomorrow" as his theme song,i became an implacable foe. and whatever "i'm pissing blood!" red expresses, it's not taste.
what i think you want to project is total assurance that you are in fact the center of power in the room. screeching "look at meeee!", putting it mildly, doesn't do that. even if you're 5'3" or whatever it may be, i'd try to express dignified, perfect self-assurance.
so you could think of this as part of our cultural adjustment to women in power. but part of that in turn is women's adjustment to their own power. now a secretary of state or speaker of the house has no reason feel insecure in her power. if she doesn't like you, you can expect a visit from the irs or the us army or whatever. compared to you, they're colossi, little gods who hold over you the power of life and death. they don't need to emphasize that at all; it's much more disconcerting when the power itself is the only radiance. that's why no one dresses in imperial robes anymore except catholic cardinals: the hooha isn't convincing anymore; but the implacable stripped-bare reality is impossible to deny.