Think of the treaty as a non-binding suggestion. If it’s better for Americans to toss it in the trashcan, though, in the trashcan it goes (“not sure” responses, constituting 25% of the total, are excluded):
The social contract doesn’t bind individuals and the international contract doesn’t bind nations. Consent is not the default. Each sovereign entity may choose to opt in to a contractual agreement, but if he or it does not, he or it are not morally bound by the contract’s terms.