What more do you want? The 14th Amendment arguably covers this at the state level. But nothing in the Constitution authorizes the federal government to write or execute state laws. The states are free to write any law they wish, but those laws must pass 14th Amendment muster.
We're not that far apart on this -- the only difference is that you see this as a federal government issue, and I see it as a state government issue. At either level, they're still constrained by the same set of Constitutional guidelines.
You can’t read the founding paragraph of the Declaration, the Preamble to the Constitution, or the Fifth and Fourteenth Amendments to that document, and conclude reasonably that any State or individual has the right to alienate the God-given right to life, anywhere in the territory of the United States.
Indeed. Every one of the States' constitutions open with a clause that protects the unalienable right to life. The only way you can get around that, just as in our federal Constitution, is to argue, insensibly, that unborn babies are not persons.