Americans today vacillate over national security and government power. We want an effective intelligence community, but we don’t want too much surveillance or collection. We want to rein in the NSA, but we also wax outraged when it does not connect the dots. We want to capture the enemy, but we want to close Guantanamo Bay. We want to kill the enemy, but drone strikes make us uncomfortable. The further we get from the September 11, 2001 attacks, the less tolerant we are of strong government actions to prevent future attacks—except when something like the Boston marathon bombing happens, when we immediately want to know why the government did not do more and know more.

Our vacillations are honorable, and they are also very old. The Father of the Constitution, James Madison, himself went back and forth over the course of his long career—as Founder, as opposition leader, and then as President—about how security should inflect the powers we invest in government. In Madison’s vacillations, we see fascinating prototypes of our own....