Is Any Part of the Constitution Unconstitutional?

Sounds like an impossibility due to self-referential logic, but...
The American Spectator : Is Any Part of the Constitution Unconstitutional?

The 17th Amendment to the Constitution, which provides for the direct popular election of senators, was enacted in 1913, at the height of the Progressive Era. Originally, the Constitution had provided for state legislatures to appoint U.S. senators, a realistic reflection that the Constitution was a compact of sovereign states. It meant that senators would not be focused on public campaigning; they could do what they were elected to do. They would represent the interests of the states that sent them -- not the people in the states, but the states as sovereign entities.

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As the Tea Partiers educate themselves about what is good law and can stay, and what is bad law and must be purged, I would urge them to take a second look at the 17th Amendment and consider whether more democracy is what we want, or if it's really more checks on the voracious federal appetite for power that we need.

No, not unconstitutional. But maybe a bad idea.