Something to note as well is what our State and Federal elected officials swear to.

U.S. Federal and Military Oath of Office

An individual, except the President, elected or appointed to an office of honor or profit in the civil service or uniformed services, shall take the following oath:
''I, __________, do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I take this obligation freely, without any mental reservation or purpose of evasion; and that I will well and faithfully discharge the duties of the office on which I am about to enter. So help me God.''

Each person enlisting in an armed force shall take the following oath:
''I, __________, do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; and that I will obey the orders of the President of the United States and the orders of the officers appointed over me, according to regulations and the Uniform Code of Military Justice. So help me God."

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For the President, based on Article II, Section I of the U.S. Constitution, the simple oath is this:
" I, _________________, do solemnly swear, that I will faithfully execute the office of President of the United States, and will to the best of my ability, preserve, protect and defend, the Constitution of the United States, so help me God."

Members of the U.S. Armed Forces also swear this oath. For example, officers in the U.S. Navy are required to recite this:
"I, _____________, having been appointed a ______________ in the U.S. Navy under the conditions indicated in this document, do accept such appointment and do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic, that I will bear true faith and allegiance to the same; that I take this obligation freely, without any mental reservation or purpose of evasion; and that I will well and faithfully discharge the duties of the office on which I am about to enter, so help me God."

Further, individual American states also provide within their state constitutions that state officeholders should swear to uphold the state constitution. Consider New Hampshire:
"I, _____________, do solemnly and sincerely swear and affirm that I will faithfully and impartially discharge and perform all duties incumbent on me as _____________________, according to the best of my abilities, agreeably to the rules and regulations of this Constitution and laws of the State of New Hampshire. So help me God."