Speech at Ave Maria Law School

Again, the link is broken, but here's what I had copied from this speech by Justice Clarence Thomas:

Think of a speck of dust in this room. One single speck. There is nothing in our jurisprudence that says the government can't regulate that one individual speck of dust in Ann Arbor, Mich., in Crowne Plaza Hotel. Now explain to me, when you read the constitution, where the authority to regulate that speck comes from? If the government can regulate that speck, tell me what it can't regulate from the national level.

The mere fact that we don't even bother to be concerned by the absence of a limiting principle on the national government is a huge threat.

Where has large centralized government existed compatibly with individual liberty? I ask this question and I wish somebody someday would give me a good answer.