That raises a lot of questions. What threshold of evidence, if any, must a high-ranking official meet to determine that someone is Al Qaeda? The burden is apparently less onerous than two witnesses testifying in open court, which the Constitution requires for a treason conviction. But the memo specifies neither an evidential threshold nor a protocol for meeting it. That is troubling.

But the part of the memo worth dwelling on most, at least until legal experts offer deeper analysis than I confidently can, is the portion that deals with "an imminent threat of violent attack."

On reading the document, that clause is sort of reassuring. After all, there aren't that many circumstances when an attack is imminent. It would seem to severely constrain extrajudicial assassinations.

As it turns out, however, the memo reassures the reader with the rhetorically powerful word "imminent," only to define imminence down in a way that makes it largely meaningless -- so much so that it's actually reminiscent of George W. Bush's misuse of imminent to characterize the threat posed by Iraq. It's difficult to adequately emphasize how absurd this part of the document becomes. What does it mean, for you personally, when you hear that someone poses "an imminent threat of violent attack against the United States"? Do you have an answer in your head?

Okay, here's the darkly hilarious passage where the Obama Administration tries to disabuse you of it:



Certain aspects of this legal framework require additional explication. First, the condition that an operational leader present an "imminent" threat of violent attack against the United States does not require the United States to have clear evidence that a specific attack on U.S. persons will take place in the immediate future.



You can't make this stuff up.

And remember the part about how killings were only kosher if capture wasn't feasible? Well, there's a caveat:



Regarding the feasibility of capture, capture would not be feasible if it could not be physically effectuated during the relevant window of opportunity or if the relevant country were to decline to consent to a capture operation. Other factors such as undue risk to U.S. personnel conducting a potential capture operation also could be relevant. Feasibility would be a highly fact-specific and potentially time-sensitive inquiry.



There's much more to the memo. Stay tuned for more analysis in this space. For now, the takeaway is that the Obama Administration took a process that is supposed to constrain the president within the law's confines; nodded toward the notion that they can kill only if capture is infeasible and the threat of attack imminent; and then qualified those constraints so drastically that it would be more honest to acknowledge that neither imminence nor infeasible capture are really required.