Article II of the U.S. Constitution twice imposes a duty of faithful execution on the President, who must take Care that the Laws be faithfully executed and take an oath or affirmation to \u27faithfully execute the Office of President. These Faithful Execution Clauses are cited often, but their background and original meaning have never been fully explored. Courts, the executive branch, and many scholars rely on one or both clauses as support for expansive views of presidential power, for example, to go beyond standing law to defend the nation in emergencies; to withhold documents from Congress or the courts; or to refuse to fully execute statutes on grounds of unconstitutionality or for policy reasons. This Article is the first to explo...