What was the major effect of the Roosevelt Corollary to the Monroe Doctrine?

From President Theodore Roosevelt’s State of the Union Address to Congress, 1904:

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It is not true that the United States feels any land hunger or entertains any projects as regards the other nations of the Western Hemisphere save such as are for their welfare. All that this country desires is to see the neighboring countries stable, orderly, and prosperous. Any country whose people conduct themselves well can count upon our hearty friendship. If a nation shows that it knows how to act with reasonable efficiency and decency in social and political matters, if it keeps order and pays its obligations, it need fear no interference from the United States. Chronic wrongdoing, or an impotence which results in a general loosening of the ties of civilized society, may in America, as elsewhere, ultimately require intervention by some civilized nation, and in the Western Hemisphere the adherence of the United States to the Monroe Doctrine may force the United States, however reluctantly, in flagrant cases of such wrongdoing or impotence, to the exercise of an international police power. If every country washed by the Caribbean Sea would show the progress in stable and just civilization which with the aid of the Platt Amendment Cuba has shown since our troops left the island, and which so many of the republics in both Americas are constantly and brilliantly showing, all question of interference by this Nation with their affairs would be at an end. Our interests and those of our southern neighbors are in reality identical. They have great natural riches, and if within their borders the reign of law and justice obtains, prosperity is sure to come to them. While they thus obey the primary laws of civilized society they may rest assured that they will be treated by us in a spirit of cordial and helpful sympathy. We would interfere with them only in the last resort, and then only if it became evident that their inability or unwillingness to do justice at home and abroad had violated the rights of the United States or had invited foreign aggression to the detriment of the entire body of American nations. It is a mere truism to say that every nation, whether in America or anywhere else, which desires to maintain its freedom, its independence, must ultimately realize that the right of such independence can not be separated from the responsibility of making good use of it.

In asserting the Monroe Doctrine, in taking such steps as we have taken in regard to Cuba, Venezuela, and Panama, and in endeavoring to circumscribe the theater of war in the Far East, and to secure the open door in China, we have acted in our own interest as well as in the interest of humanity at large. There are, however, cases in which, while our own interests are not greatly involved, strong appeal is made to our sympathies. Ordinarily it is very much wiser and more useful for us to concern ourselves with striving for our own moral and material betterment here at home than to concern ourselves with trying to better the condition of things in other nations. We have plenty of sins of our own to war against, and under ordinary circumstances we can do more for the general uplifting of humanity by striving with heart and soul to put a stop to civic corruption, to brutal lawlessness and violent race prejudices here at home than by passing resolutions and wrongdoing elsewhere. Nevertheless there are occasional crimes committed on so vast a scale and of such peculiar horror as to make us doubt whether it is not our manifest duty to endeavor at least to show our disapproval of the deed and our sympathy with those who have suffered by it. The cases must be extreme in which such a course is justifiable. There must be no effort made to remove the mote from our brother’s eye if we refuse to remove the beam from our own. But in extreme cases action may be justifiable and proper. What form the action shall take must depend upon the circumstances of the case; that is, upon the degree of the atrocity and upon our power to remedy it. The cases in which we could interfere by force of arms as we interfered to put a stop to intolerable conditions in Cuba are necessarily very few. Yet it is not to be expected that a people like ours, which in spite of certain very obvious shortcomings, nevertheless as a whole shows by its consistent practice its belief in the principles of civil and religious liberty and of orderly freedom, a people among whom even the worst crime, like the crime of lynching, is never more than sporadic, so that individuals and not classes are molested in their fundamental rights—it is inevitable that such a nation should desire eagerly to give expression to its horror on an occasion like that of the massacre of the Jews in Kishenef, or when it witnesses such systematic and long-extended cruelty and oppression as the cruelty and oppression of which the Armenians have been the victims, and which have won for them the indignant pity of the civilized world.

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