Sheryl Sandberg's well-researched new book, Lean In, focuses on helping women who aspire to careers identify and overcome negative societal messages they have internalized over the years – old scripts that undermine women’s self-confidence and hold them back from achieving their full potential on the job. It's not every day that a high-achieving woman proclaims herself a feminist, so I have been surprised by the amount of venom heaped on Sandberg’s book. Some commentators complain that Sandberg places too little emphasis on the institutional barriers and prejudices that stand in the way of...