Why do I hold Sarah Palin to a more exacting standard than I do David Frum? Simple: because Palin and Frum fulfill different roles in the conservative movement. Palin is a political leader; Frum an intellectual leader. As an intellectual leader, Frum has much greater leeway — and an obligation really — to challenge conservative orthodoxy. Palin, by contrast, is abandoning conservative policy positions that she does not yet fully understand and has not yet fully thought through.