Congress has been exempting itself from laws that regular citizens must follow. The recent problem with insider trading in Congress is an example. Rather than go after each and every provision slipped into various bills, including ones like relief for Hurricane Sandy victims, it should be in the Constitution that no law can be exempted from Congress, the Executive Branch, or Judiciary.
The Founding Fathers may have felt this was self evident from the Declaration of Independence and the organization of government in the Constitution. But even then, the first Ten Amendments were written, and the ability for the Constitution to be adaptable to the times is its greatest strength.
Being elected to Congress is no longer an act of citizenship, but entrance into potential plutocracy.