Oona A. Hathaway[*] [This essay is available in PDF at this link] The last several decades have witnessed a dramatic decline in the capacity of the U.S. Congress to constrain the president’s unilateral decisions to send the United States to war. That erosion of congressional authority has accelerated since the terrorist attacks of September 11, 2001. … Continue reading How the Erosion of U.S. War Powers Constraints Has Undermined International Law Constraints on the Use of Force