On Tuesday, Michael Isikoff of NBC News published a 16-page white paper that outlines the government's secret justification for the extrajudicial killing of an American believed to be affiliated with a terrorist organization.

One aspect of what the ACLU's Hina Shamsi considers “a profoundly disturbing document” is that it relies on a controversial section of the 2012 National Defense Authorization Act (NDAA)—which is already at the center of an ongoing lawsuit that will be heard in the United States Court of Appeals for the Second Circuit on February 6.

From the white paper:

The President has the authority to respond to the imminent threat posed by al-Qa'ida and its associated forces, arising from … [the Constitution, self defense under international law,] Congress's authorization of the use of all necessary and appropriate military force against this enemy, and the existence of an armed conflict with al-Qa'ida under international law.

The Authorization of Use of Military Force (AUMF), passed by Congress in October 2001, gives the president authority "to use all necessary and appropriate force against those ... [who] aided the terrorist attacks that occurred on September 11, 2001 or harbored such organizations or persons."

The original AUMF, however, says nothing about the "imminent threat posed by al-Qa'ida and its associated forces" in the present day. That language appears in section 1021 of the 2012 NDAA:

... The President also has the authority to detain persons who were part of or substantially supported, Taliban or al-Qaida forces or associated forces that are engaged in hostilities against the United States or its coalition partners, including any person who has committed a belligerent act, or has directly supported hostilities, in the aid of such enemy forces.

In the ongoing lawsuit challenging the NDAA's indefinite detention provisions, Judge Katherine Forrest ruled that the added language —which the government argued was simply an "affirmation" the AUMF—is unconstitutionally vague. She later said that section 1021 appeared to be a retroactive legislative fix "to provide the President (in 2012) with broader detention authority than was provided in the AUMF in 2001."

In the white paper, the government applies this broad authority to extrajudicial killing when it states that "a targeted killing of a U.S. citizen who has joined al-Qa'ida or its associated forces would be lawful under U.S. and international law" because "Congress has authorized the President to use all necessary and appropriate force against [al-Qaida or associated forces]."

Yet it is section 1021 of the 2012 NDAA, and not the 2001 AUMF, that authorizes the use of broad executive powers ina perpetual war against al-Qaeda and "associated forces" that could continue indefinitely.

Therefore if this part of the NDAA is blocked, the government's argument for both extrajudicial killings and indefinite detention of U.S. citizens would fall apart.

In the words of NDAA plaintiff Tangerine Bolen: "Our lawsuit is the lock on Pandora's box. And Pandora's box is the overly broad application of the AUMF… [Blocking NDAA §1021] is to suddenly and sharply delimit powers upon which President Obama has come to rely wrongfully. He never should've had these powers."