1. Limiting voting to citizens.
2. Advice and Consent of the Senate.
3. Unlawful search and seizure.
4. Unlawful takings.
5. Self-defense with one's own arms.
6. Petitioning the government for redress of grievances.
-PJ
Just a technical point: the Constitution does not explicitly limit voting to citizens, but every state has a law that makes American citizenship among the requirements for voting, and to the best of my knowledge, such a requirement has been present in every state since the country's founding.
Of course the Left has cheated and concocted various schemes in various states to attempt to violate such laws, because alien voting helps their cause.