The title of this article should read, "Obama Praises the CIA Execution of a US Citizen".
Here is what Glenn Greenwald who was trained in constitutional law writes about this incident:
From an authoritarian perspective, that's the genius of America's political culture. It not only finds way to obliterate the most basic individual liberties designed to safeguard citizens from consummate abuses of power (such as extinguishing the lives of citizens without due process). It actually gets its citizens to stand up and clap and even celebrate the destruction of those safeguards.