You merely point out an absence of facts relating to natural law. Once people had accurate facts, they corrected their errors. This guy helped a lot.
While we are on the topic, there is a distinct difference in what is regarded as "natural law" based on your foundational premise of government.
If you follow the Monarchist version of natural law, it leads to certain conclusions... mainly that the King Owns you.
If you follow the American version of natural law, you own yourself. In other words, you have the right to leave a country you don't like, and become a member of a country you do like.
Under the English version of natural law, you do not. From their foundational assumption that the King rules by divine right, that the King is the Servant of God and reigns on Earth because it is God's will, it is a rational conclusion that your owe perpetual allegiance to the King, and that if you are born on his land, you are his servant.
If your foundational assumption does not rely on rule by Divine Right, then you can rationally conclude that Individuals are not feudally bound to their liege Lord, and can exercise their own natural rights, first among them being the right to live. Others include the right to go where you will and do what you wish.
Not being bound to the land means your character is determined by your nature, (inheritance, both genetic and otherwise) rather than by who owns the land you stand upon. You inherit your father's national character, in the same manner you inherit his name.
People have always had the right to expatriate regardless of whether they believe in natural law. Slaves and indentured servants did not own themselves for the first 89 years of the republic.