President Barack Obama is starting to channel his inner Cheney. For years, Obama talked about the limits on presidential power. Now, driven either by principle or political expediency, he's working to build and maintain a powerful presidency that pushes the edge of what it can do, while often telling Congress and the courts to mind their own business. In the last week alone, he refused a subpoena to share Justice Department emails with Congress, told courts he doesn't have to justify his claimed power to assassinate suspected terrorists, and decided to stop deporting certain illegal immigrants even though Congress has...