I have posted my new essay Constitutional War Initiation and the Obama Presidency (American Journal of International Law, forthcoming 2016) on SSRN. It is part of the Journal's forthcoming "agora" on President Obama's war powers legacy, also including essays from Curtis Bradley (Duke) and Jack Goldsmith (Harvard), Ashley Deeks (Virginia), Ryan Goodman (NYU) and Rebecca Ingber (Boston Univ). Here is the abstract of my essay:
This essay assesses the constitutionality of President Obama's uses of military force. It uses two baselines -- the Constitution's original meaning, and the practice of U.S. presidents between the end of the Vietnam War and the beginning of the Obama presidency. Although President Obama has been criticized for expanding the president's unilateral powers to use military force, this essay concludes that these claims may overstate. Taken as a whole, the legacy of the Obama administration may be to decrease rather than expand the war initiation powers of the presidency.
Specifically, this essay considers President Obama's use of military force under four headings: (1) the use of force against the Al Qaeda terrorist organization and its affiliates; (2) the use of force against the Islamic State; (3) the use of force against the Qaddafi government in Libya; and (4) the threatened use of force against the Assad government in Syria. It notes that the President has principally justified the first two as authorized by statute -- and, at least in the case of the Islamic State, through very aggressive readings of the authorizing statute. While aggressive statutory readings may expand the presidency's flexibility in using force, they do not expand the presidency's claims to independent constitutional power. Indeed, to the extent aggressive statutory readings substitute for aggressive claims of independent authority, they may be seen to undercut arguments for independent authority.
With respect to Libya, this essay agrees with widespread critical commentary that the President claimed independent war initiation authority beyond the powers conveyed by the original Constitution and beyond powers established by modern consistent and widely accepted presidential practice. However, it notes several limiting features of the Libya episode as a precedent for future action. Moreover, it notes that the Libya episode may be balanced by subsequent events with respect to Syria, in which the President declined to use unilateral force against the Assad regime.
To be clear, I am not retreating at all from my view that the 2011 Libya intervention was unconstitutional by just about any measure. But as the essay explains, I think President Obama's war initiation record taken as a whole is not as aggressive, and will not set as many bad precedents, as some commentators suggest.