Treaty noncompliance through conflicting domestic law wrecks the effectiveness of US leadership
Bellinger et al, 13 – Council of Record for the Brief of Former State Department Legal Advisors (John, Amicus Brief in Carole Anne Bond v. United States of America, SCOTUS 12-158, http://www.americanbar.org/content/dam/aba/publications/supreme_court_preview/briefs-v2/12-158_resp_amcu_fsdl.authcheckdam.pdf
The Constitution reflects the Framers’ recognition, based on experience under the Articles of Confederation, that the power to enter and implement treaties must rest with the national government in order for the United States to be an effective sovereign on the international stage. Those same imperatives pertain today. The power to make treaties and the need to implement them are inherently intertwined. If Congress cannot fully implement a validly executed treaty, the United States may be unable to honor its international commitments. This would undercut the United States’ foreign policy priorities, diminish the President’s leverage to pressure nations to comply with their own obligations, and injure the United States’ credibility as a world leader—not to mention undermine the efficacy of the treaty itself.