The Constitution is the "supreme Law of the Land." It is controlling as to all officials of the three Branches of the Federal government--Executive, Legislative and Judicial--with regard to all of their pronouncements, actions, decisions, agreements and legislative Acts. Each of them is sworn, by oath of office, to support the Constitution
ONLY. To be valid, any treaty must be strictly in conformity to--free from any conflict with--the Constitution. A treaty is like a Federal law in this respect.
The Constitution is supreme over laws and treaties; it expressly states (Article VI, Section 2) that: "This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land . . ." This means that any such Law (Act of Congress) which violates the Constitution is automatically made null and void to start with--nullified by the Constitution itself--and therefore cannot be a part of the "supreme Law of the Land." This is also true as to treaties.
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