When Laura Bush became first lady four years ago she didn't know just how powerful her position in the White House would be. "It took me a while to really realize what podium I had, as Lady Bird Johnson says," Mrs. Bush said, recalling the reaction from women nationwide after she made her first radio address about the women of Afghanistan. "And, I think, you know, you kind of hear and certainly you watch your whole life — I certainly had a very close view of the role of the women in the White House, but it really takes a...