Not much.  Mark Schmitt observes:

Roughly speaking, there have been four great showdowns over abuse of executive power in modern U.S. history.

The earliest has to do with domestic surveillance by the CIA, and other ill-conceived schemes, as revealed by the 1975 Church Committee hearings.

The second, closely overlapping the first, involved all the excesses of the Nixon administration, including Watergate itself, the "Plumbers," the secret bombing of Cambodia, Kissinger"s wiretapping of staffers, etc.

The third, the Iran-Contra scandal in the Reagan Administration, seems quaint compared to the fourth, the Bush administration"s NSA domestic surveillance program, and the broader assertion of executive authority to torture and otherwise ignore international law.

These episodes have certain themes in common. Yes, one of them is that they were all hatched in the first term of Republican presidencies and revealed only after reelection…