United States Constitution bars religion as a condition to enter public office
According to the constitution of the United States, religion cannot be a reason to bar someone from taking up public office:
Article 6 - Debts, Supremacy, Oaths
All Debts contracted and Engagements entered into, before the Adoption of this Constitution, shall be as valid against the United States under this Constitution, as under the Confederation.
This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.
The Senators and Representatives before mentioned, and the Members of the several State Legislatures, and all executive and judicial Officers, both of the United States and of the several States, shall be bound by Oath or Affirmation, to support this Constitution; but no religious Test shall ever be required as a Qualification to any Office or public Trust under the United States.
The clause just before the one that contains the religious reference is called the “Supremacy Clause”. It indicates that the constitution of the United States always take precedence over state laws. This supremacy clause makes religious test clauses in the legislation of constitution of individual states unenforceable. Unfortunately for atheists, this unenforceability does not always seem to deter religious fanatics in the US, usually Christians, from discriminating against them, pestering them and suing them into financial oblivion.
