That's a rather uncontroversial position with respect to a uniformed military force; it's a murky position, indeed, applied to a criminal organization operating outside the law of war. As a December report from Human Rights First notes, "Targeted killing is lawful in an armed conflict pursuant to the rules of international humanitarian law, also known as the law of armed conflict (IHL/LOAC), which permit lethal targeting of members of enemy armed forces and others while they directly participate in hostilities." It's doubtful whether al Qaeda, much less the undefined "associated groups," qualifies under that definition.
National Journal's Ron Fournier argues that, "If killing Americans with no due process is OK when their alleged crime is consorting with al-Qaida, it's not a huge intellectual leap to give government officials the same judge-and-jury authority over other heinous acts such as mass murder, drug trafficking, and child pornography." That overstates the case. Despite the use of the "war on" rhetoric to describe our policies against domestic criminal conduct, nobody suggests a state of war exists with domestic criminal groups. Further, the fact that people engaging in those activities can feasibly be captured and given due process would rule them out for extra-judicial killings even under the broad mandate of the DOJ white paper.
There's no denying that al Qaeda poses a unique threat to the safety of American citizens. Operating in ungoverned spaces of Pakistan, Yemen, and elsewhere, they're largely out of the reach of traditional law enforcement. If al-Awlaki or Khan were performing the exact same acts in Cleveland—or, indeed, London, Paris, or Sydney—they would have been targeted for arrest and extradition, not assassination.
Even so, American citizens should nonetheless be wary of granting the president the power to single out citizens for killing based simply on his own judgment. Aside from being plainly unconstitutional, it's simply too much trust to place in a single individual. At the very least, the rules ought to be spelled out in legislation that has passed both Houses of Congress and survived judicial scrutiny for constitutionality rather than made internally.
Further, in addition to checks and balances, there has to be more transparency. The notion that the government can compile a list of citizens for killing, not tell anyone who's on it or how they got there, is simply un–American. Surely, a modern version of a WANTED: DEAD OR ALIVE notice could be publicly circulated, with a listing of the particulars. Maybe the named individual would turn himself in rather than wait for the drones to find him. Or maybe he'd hire an attorney to present evidence he's not actually an imminent threat to American citizens.
For centuries, civilized societies have understood that even wars must be fought according to rules, which have developed over time in response to changing realities. Rules are even more important in endless, murky wars such as the fight against Islamist terror groups. Currently, we're letting whomever is in the Oval Office pick and choose from among the existing rules, applying and redefining them based on his own judgment and that of his advisors. We can do better.
James Joyner is managing editor of the Atlantic Council.