I would disagree with you, vehemently. The idea of natural rights is founded in our Declaration of Independence, enumerated in the clause:
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness. — That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed
Taking the foundation of our country, the right to establish a governance, and everything else that was listed in that Declaration, and saying that our Constitution doesn't have "natural right", is completely why they included the First Ten Amendments. If the law said we didn't have the right to free speech, and you're supporting ONLY the "law" (as your position indicates) then you have no "free speech" and it isn't a right.
It is people like you scare the crap out of people like me, because you think rights are allowed and/or established by law, rather than exist above and apart from the law. The moment you talk about "legality" when speaking to rights, you've lost me.
The first ten Amendments enumerate natural rights, and were inserted because of concerns of people like you.