- National honor is the national property of the highest value.
- First Inaugural Address (March 4, 1817)
- The mention of Greece fills the mind with the most exalted sentiments and arouses in our bosoms the best feelings of which our nature is capable.
- Message to Congress (December 1822)
The Monroe Doctrine (December 2, 1823) 
- The American continents ... are henceforth not to be considered as subjects for future colonization by any European powers.
- In the wars of the European powers in matters relating to themselves we have never taken any part, nor does it comport with our policy so to do.
- We owe it, therefore, to candor and to the amicable relations existing between the United States and those powers to declare that we should consider any attempt on their part to extend their system to any portion of this hemisphere as dangerous to our peace and safety. With the existing colonies or dependencies of any European power we have not interfered and shall not interfere. But with the Governments who have declared their independence and maintain it, and whose independence we have, on great consideration and on just principles, acknowledged, we could not view any interposition for the purpose of oppressing them, or controlling in any other manner their destiny, by any European power in any other light than as the manifestation of an unfriendly disposition toward the United States.