I haven't heard many people argue that the first 8 Amendments, from the time they were ratified, bound the states. In fact, Madison, when he drafted the Bill of Rights proposed one that read:
No state shall violate the equal rights of conscience, or the freedom of the press, or the trial by jury in criminal cases
a proposed amendment that was rejected although Madison belived it to be the most important of his proposed amendments.
It seems hard for Americans today to appreciate how connected Americans were to their states and how fearful they were of the federal government. You see it even in the quotes over the Blaine Amendment in 1875...even then, American politicians still did not want the federal government defining fundamental rights or their scope in their states.
The strange irony of the Bill of Rights is that they were seen by many of the Framers as unnecessary. Even Federalists like Hamilton acknowleged that they were only prohibiting the federal government from doing things it did not have the power to do anyway. In Federalist 84,. Hamilton writes:
I go further, and affirm that bills of rights, in the sense and in the extent in which they are contended for, are not only unnecessary in the proposed constitution, but would even be dangerous. They would contain various exceptions to powers which are not granted; and on this very account, would afford a colourable pretext to claim more than were granted. For why declare that things shall not be done which there is no power to do? Why for instance, should it be said, that the liberty of the press shall not be restrained, when no power is given by which restrictions may be imposed?
In 1821, Madison described the Bill of Rights as "those safe, if not necessary, and those politic, if not obligatory, amendments."
The concern was to provide some minimal level of protection against the potential for the federal government to one day take enough power that it could violate fundamental rights not protected under state constitutions. The push for the Bill of Rights came mostly from the AntiFederalists (who, in many cases, objected to the whole idea of creating this federal government and would not, in a million years, have acceded to having the new US Constitution dictate how states could govern internally)
The 9th Amendment, works together with the 10th Amendment, and these two amendments were added at the insistence of the Virginia and NC delegations that were concerned that the Bill of Rights might, constructively or by implication, expand the powers of the federal government vis-a-vis the states. This is evident from the writings from the state ratifying conventions, from the writings of Madison himself and particularly from Madison's speech before Congress regarding the chartering of the Bank of the United States...which Madison himself argued was unconstitutional because "latitudinal constructions" (Madison's phrase) of enumerated powers were unconstitutional. Madison speaks throughout his speech about federal usurpation of the "rights of states" to charter banks. Mind you, this speech, which focused on the subject of the 9th Amendment was given while the Virginia delegation was debating the Bill of Rights
In proposing the Bill of Rights, Madison stated in Congress:
It has been objected also against a bill of rights, that, by enumerating particular exceptions to the grant of power, it would disparage those rights which were not placed in that enumeration and it might follow by implication, that those rights which were not singled out, were intended to be assigned into the hands of the general government, and were consequently insecure. This is one of the most plausible arguments I have ever heard urged against the admission of a bill of rights into this system; but, I conceive, that may be guarded against. I have attempted it, as gentlemen may see by turning to the last clause of the 4th resolution.
What was the last clause of the 4th Resolution?:
The exceptions here or elsewhere in the Constitution, made in favor of particular rights, shall not be so construed as to diminish the just importance of other rights retained by the people, or as to enlarge the powers delegated by the Constitution; but either as actual limitations of such powers, or as inserted merely for greater caution.
It was this clause which ultimately became the 9th and 10th Amendments...it was not individual rights the US Constitution aimed to protect...rather it aimed to create a federal government with emough powers to deal with the issues for which it was created...without giving it so much power that it trampled the rights of the states...individual, natural rights were topics left to the state governments and state constitutions
Especially with so much Conservative support for Gary Hart's and Andrew Young's Patriot Act.