Good point - absent a constitutional amendment, Article I, Section 6 of the U.S. constitution supersedes any TSA rules and regulations because of the clause in this sentence regarding senators and representatives:
"They shall in all Cases, except Treason, Felony and Breach of the Peace, be privileged from Arrest during their Attendance at the Session of their respective Houses, and in going to and returning from the same; and for any Speech or Debate in either House, they shall not be questioned in any other Place."
However, the TSA has in the past also violated diplomatic immunity of traveling diplomats with impunity, so at this point I'd say they have become an unstoppable law unto themselves.