The idea from Washington’s Farewell Address that was incorporated in the Monroe Doctrine is the principle of non-intervention in the affairs of other nations. Washington's Farewell Address emphasized the importance of avoiding entanglements in foreign conflicts and advised against forming permanent alliances. The Monroe Doctrine, announced by President James Monroe in 1823, essentially extended this principle to the Americas. It stated that the United States would consider any European attempt to colonize or interfere in the Western Hemisphere as a threat to its own security and interests. This principle of non-intervention laid the foundation for the Monroe Doctrine and became a central aspect of U.S. foreign policy for many years to come.
