The Power to Threaten War

Existing legal scholarship about constitutional war powers focuses overwhelmingly on the President\u27s power to initiate military operations abroad and the extent to which that power is constrained by Congress. It ignores the allocation of legal power to threaten military force or war, even though threats – to coerce or deter enemies and to reassure allies – is one of the most important ways in which the United States government wields its military might. This paper fills that scholarly void, and draws on recent political science and historical scholarship to construct a richer and more accurate account of the modern presidency\u27s powers to shape American security policy and strategy. As a descriptive matter, the swelling scope of the president’s practice in wielding threatened force largely tracks the standard historical narrative of war powers shifting from Congress to the President. Indeed, adding threats of force to that story might suggest that this shift in powers of war and peace has been even more dramatic than usually supposed, at least in terms of how formal congressional checks are exercised. This paper shows, however, that congressional checks and influence – even if not formal legislative powers – operate more robustly and in different ways to shape strategic decision-making than usually supposed in legal debates about war powers, and that these checks and influence can enhance the potency of threatened force. As a prescriptive matter, this paper also shows that examination of threatened force and the credibility requirements for its effectiveness calls into question many orthodoxies of the policy advantages and risks attendant to various allocations of legal war powers, including the existing one and proposed reforms. Instead of proposing a policy-optimal solution, this paper concludes that the allocation of constitutional war powers is – and should be – geo-politically and strategically contingent; the actual and effective balance between presidential and congressional powers over war and peace in practice necessarily depends on fundamental assumptions and shifting policy choices about how best to secure U.S. interests against potential threats