Our smartest presidents ever?

Via The Belmont Club, I found this Nora Ephron post on the Clinton/Chris Wallace controversy which obsesses over the fact that Clinton's socks were falling down during the interview. I remember Bill's fingers, not his calves, but here's what really caught my eye:

How does one of the smartest men ever elected president end up sandbagged by Chris Wallace?

I suppose that depends on what your definition of smart is.