President Obama seems more committed to protecting national security than promoting civil liberties and privacy rights, which puts him firmly in the tradition of most of his predecessors, says presidential historian Robert Dallek.

"It's not surprising," Dallek tells me. "This is what presidents do."

Dallek says one reason is that there are "real national security concerns" that preoccupy every commander in chief. In Obama's case, they include fear of a repetition of the terrorist attacks of 9/11 and the Boston Marathon bombings....