"Treaties do not have the power to override the constitution itself."
While I agree that should be the case, it is sadly a bit more nuanced[1]:
Under the Constitution as originally understood, the short answer is: “No, a treaty can’t override the Constitution. The treaty has the force only of a statute, not of a super-constitution.”
But the full answer is more complicated. This is because the Founding-Era evidence does suggest that the Constitution enables the federal government to acquire significant—although not unlimited—additional power by entering into treaties.
...
In 1783, the Confederation Congress debated and approved a treaty with the Netherlands despite recognizing that the terms of the treaty might interfere somewhat with freedom of religion. Thus Congress impacted the exercise of religion, an area over which the Articles otherwise gave it no authority.
While I agree that should be the case, it is sadly a bit more nuanced[1]:
Under the Constitution as originally understood, the short answer is: “No, a treaty can’t override the Constitution. The treaty has the force only of a statute, not of a super-constitution.”
But the full answer is more complicated. This is because the Founding-Era evidence does suggest that the Constitution enables the federal government to acquire significant—although not unlimited—additional power by entering into treaties.
...
In 1783, the Confederation Congress debated and approved a treaty with the Netherlands despite recognizing that the terms of the treaty might interfere somewhat with freedom of religion. Thus Congress impacted the exercise of religion, an area over which the Articles otherwise gave it no authority.
[1] http://tenthamendmentcenter.com/2013/11/13/can-treaties-over...