"THE Conventions of a number of the States having at the time of their adopting the Constitution, expressed a desire, in order to prevent misconstruction or abuse of its powers, that further declaratory and restrictive clauses should be added: And as extending the ground of public confidence in the Government, will best insure the beneficent ends of its institution"
In other words, the Bill of Rights was enacted "in order to prevent misconstruction or abuse of its powers". This is referring to the limited powers granted to the government in the constitution. Notice, the preamble doesn't say "in order to grant rights...". The bill of rights contains "further declaratory and restrictive clauses".
Thus, these clauses are not designed to create or grant rights, but are of a "declaratory and restrictive" nature.
The constitution does not create any rights. There is no such thing, in the american form of government, as "constitutional rights". People often use this phrase when referring to the Bill of Rights, but it is imprecise, because the Bill of Rights doesn't grant rights. IT doesn't say "the people shall have the right of free speech", instead it says "Congress shall make no law ... abridging the freedom of speech, or of the press;"
The right of free speech, as recognized by the First Amendment, precedes and predates the constitution.
The constitution is a document constructed under a theory of natural rights, by a group of men, many of whom had just fought off a government they considered oppressive because it didn't recognize their natural rights.
Every right, IP, or not, precedes the constitution, they are not granted by the constitution.
Thus, where the constitution says: "The Congress shall have Power ... To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."
The use of the word "securing" is deliberate.
I'm not going to debate whether intellectual property is a natural right or not. (But I wonder, if you come up with an invention but don't tell anybody, isn't that a natural property right? I mean, to say that you don't' have a right to it, would be to say that others have the right to forcibly take it from you, wouldn't it?)
My point is simply that the constitution doesn't grant any rights, rights precede it. The constitution gives the federal government limited and enumerated powers. And the federal government does not have the power to pass SOPA, both because there is no enumerated power to do what it does, and because the first amendment forbids it.
The question of whether IP is a natural right is a separate one, and opposition to soap on constitutional grounds does not imply conceding it, or not.