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Theodore Roosevelt: Corollary to the Monroe Doctrine
1905
In 1902 Germany, Italy, and England blockaded the coast of Venezuela in an effort to collect debts that it had refused to pay. President Roosevelt, concerned about the presence of Europeans in the vicinity of the uncompleted Panama Canal, made a show of naval force and urged U.S. mediation. Two years later, when European powers threatened forcibly to collect debts owed them by the Dominican Republic, the United States again intervened to make the collection. In his annual messages to Congress in 1904 and 1905, Roosevelt formulated his "corollary" to the Monroe Doctrine, urging a new role for the United States -- that of international policeman for the Western Hemisphere. In the message of 1905, which is reprinted here in part, he spelled out in detail how the role was to be conceived. 
One of the most effective instruments for peace is the Monroe Doctrine as it has been and is being gradually developed by this nation and accepted by other nations. No other policy could have been as efficient in promoting peace in the Western Hemisphere and in giving to each nation thereon the chance to develop along its own lines. If we had refused to apply the doctrine to changing conditions, it would now be completely outworn, would not meet any of the needs of the present day, and, indeed, would probably by this time have sunk into complete oblivion. 
It is useful at home and is meeting with recognition abroad because we have adapted our application of it to meet the growing and changing needs of the Hemisphere. When we announce a policy such as the Monroe Doctrine, we thereby commit ourselves to the consequences of the policy, and those consequences from time to time alter. It is out of the question to claim a right and yet shirk the responsibility for its exercise. Not only we but all American republics who are benefited by the existence of the doctrine must recognize the obligations each nation is under as regards foreign peoples, no less than its duty to insist upon its own rights. 
That our rights and interests are deeply concerned in the maintenance of the doctrine is so clear as hardly to need argument. This is especially true in view of the construction of the Panama Canal. As a mere matter of self-defense we must exercise a close watch over the approaches to this canal; and this means that we must be thoroughly alive to our interests in the Caribbean Sea. 
There are certain essential points which must never be forgotten as regards the Monroe Doctrine. In the first place, we must as a nation make it evident that we do not intend to treat it in any shape or way as an excuse for aggrandizement on our part at the expense of the republics to the south. We must recognize the fact that in some South American countries there has been much suspicion lest we should interpret the Monroe Doctrine as in some way inimical to their interests, and we must try to convince all the other nations of this continent once and for all that no just and orderly government has anything to fear from us. 
There are certain republics to the south of us which have already reached such a point of stability, order, and prosperity that they themselves, though as yet hardly consciously, are among the guarantors of this doctrine. These republics we now meet, not only on a basis of entire equality but in a spirit of frank and respectful friendship, which we hope is mutual. If all of the republics to the south of us will only grow as those to which I allude have already grown, all need for us to be the especial champions of the doctrine will disappear, for no stable and growing American republic wishes to see some great non-American military power acquire territory in its neighborhood. All that this country desires is that the other republics on this continent shall be happy and prosperous; and they cannot be happy and prosperous unless they maintain order within their boundaries and behave with a just regard for their obligations toward outsiders. 
It must be understood that under no circumstances will the United States use the Monroe Doctrine as a cloak for territorial aggression. We desire peace with all the world, but perhaps most of all with the other peoples of the American continent. There are, of course, limits to the wrongs which any self-respecting nation can endure. It is always possible that wrong actions toward this nation or toward citizens of this nation in some state unable to keep order among its own people, unable to secure justice from outsiders, and unwilling to do justice to those outsiders who treat it well, may result in our having to take action to protect our rights; but such action will not be taken with a view to territorial aggression, and it will be taken at all only with extreme reluctance and when it has become evident that every other resource has been exhausted. 
Moreover, we must make it evident that we do not intend to permit the Monroe Doctrine to be used by any nation on this continent as a shield to protect it from the consequences of its own misdeeds against foreign nations. If a republic to the south of us commits a tort against a foreign nation, such as an outrage against a citizen of that nation, then the Monroe Doctrine does not force us to interfere to prevent punishment of the tort, save to see that the punishment does not assume the form of territorial occupation in any shape. 
The case is more difficult when it refers to a contractual obligation. Our own government has always refused to enforce such contractual obligations on behalf of its citizens by an appeal to arms. It is much to be wished that all foreign governments would take the same view. But they do not; and in consequence we are liable at any time to be brought face to face with disagreeable alternatives. On the one hand, this country would certainly decline to go to war to prevent a foreign government from collecting a just debt; on the other hand, it is very inadvisable to permit any foreign power to take possession, even temporarily, of the custom-houses of an American republic in order to enforce the payment of its obligations; for such temporary occupation might turn into a permanent occupation. 
The only escape from these alternatives may at any time be that we must ourselves undertake to bring about some arrangement by which so much as possible of a just obligation shall be paid. It is far better that this country should put through such an arrangement, rather than allow any foreign country to undertake it. To do so insures the defaulting republic from having to pay debt of an improper character under duress, while it also insures honest creditors of the republic from being passed by in the interest of dishonest or grasping creditors. Moreover, for the United States to take such a position offers the only possible way of insuring us against a clash with some foreign power. The position is, therefore, in the interest of peace as well as in the interest of justice. It is of benefit to our people; it is of benefit to foreign peoples; and most of all it is really of benefit to the people of the country concerned. 
This brings me to what should be one of the fundamental objects of the Monroe Doctrine. We must ourselves in good faith try to help upward toward peace and order those of our sister republics which need such help. Just as there has been a gradual growth of the ethical element in the relations of one individual to another, so we are, even though slowly, more and more coming to recognize the duty of bearing one another's burdens, not only as among individuals but also as among nations. 
Source: A Compilation of the Messages and Papers of the Presidents 1789-1897, vol. 11, James D. Richardson, ed., 1920, pp. 1131-1181.