In the 1980s, Madonna was definitely the “It” girl, or the Material Girl. But no one would ever think that she was powerless, and that’s part of her problem in this category; she’s both less and more than the usual sex symbol. For a real “It” girl of this period, we have to turn to television and Heather Locklear, the perfect good-humored blond in tight jeans, and then in power suits.