I continue to enjoy how a significant basis for their craziness is taking specific definitions out of context. Like, sure, 28 USC 3002 does say that "United States means a federal corporation", but it's the definitions section for that particular chapter of the USC and not applicable outside that context. They ignore the very first line: "As used in this chapter."

And even then, it's defining the term "United States", not saying that is what The United States, the country, is.