Remarks in Proctor, Vermont
We believe in the Monroe Doctrine, not as a means of aggression at all. It does not mean that we are aggressive toward any power. It means merely that as the biggest power on this continent, we remain steadfastly true to the principles first formulated under the Presidency of Monroe, through John Quincy Adams— the principle that this continent must not be treated as a subject for political colonization by any European power. As I say, that is not an aggressive doctrine. It is a doctrine of peace. A doctrine of defense, a doctrine to secure the chance on this continent for the states here to develop peaceably along their own lines. Now, we have formulated that doctrine. If our formulation consists simply of statements on the stump or on paper, they are not worth the breath that utters them or the paper on which they are written. Remember, that the Monroe Doctrine will be respected as long as we have a first-class, efficient navy, and not very much longer.
In private life he who asserts something, says what he is going to do, and does not back it up, is always a contemptible creature, and as a nation the last thing we can afford to do is to take a position which we do not intend to try to make good. Bragging and boasting in private life are almost always the signs of a weak man, and a nation that is strong does not need to have its public men boast or brag on its account. Least of all, does a self-respecting nation wish its public representatives to threaten or menace or insult another power. Our attitude toward all powers must be one of such dignified courtesy and respect as we intend that they shall show us in return. We must be willing to give the friendly regard that we exact from them. We must no more wrong them than we must submit to wrongdoing by them, but when we take a position, let us remember that our holding it depends upon ourselves, depends upon our showing that we have the ability to hold it.
Shame to us if we assert the Monroe Doctrine, and then, if our assertion shall be called in question, show that we have only made an idle boast, that we are not prepared to back up our words by deeds.
Theodore Roosevelt, Remarks in Proctor, Vermont Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/343498