At the Volokh Conspiracy, University of Chicago law professor Eric Posner compares the records of George W. Bush and Barack Obama when it comes to the expansion of executive power:
Thanks to Bush, Obama enjoys the legal authorities he needs to conduct the conflict with Al Qaida—and so, until our next crisis, we don't know how Obama would have acted under similar circumstances. The Obama lawyers are certainly less inclined to bloviate than the Bush lawyers were but again where it counts—have Obama's lawyers ever stopped him from going beyond the edge of legality?—we have little information and some reason for skepticism. Obama has vigorously expanded the drone program, taken the war into Pakistan, robustly defended his right to kill American citizens abroad, and opposed litigation that could expose secrets about the treatment of detainees…. And that was before the Libya intervention.
For more on the distressing similarities between Bush and Obama, don't miss Eli Lake's June 2010 Reason feature "The 9/14 Presidency: Barack Obama, like George W. Bush, is operating with war powers granted three days after the 9/11 attacks."