I wish that the term “natural law” appeared in the actual text of the Constitution. Instead the Constitution states 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; and the Judges in every State shall be bound thereby; any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.”—Article VI, Clause 2
Yes, good point. In the relevant section of the Constitution it does not include Natural Law as part of the supreme law of the land. Nor does it include British Common Law. What it does include:
Constitution
Laws made under the Constitution
Treaties