The executive government of this country in its intercourse with foreign nations is limited to the employment of diplomacy alone. When this fails it can proceed no further. It can not legitimately resort to force without the direct authority of Congress, except in resisting and repelling hostile attacks. It would have no authority to enter the territories of Nicaragua even to prevent the destruction of the transit and protect the lives and property of our own citizens on their passage. It is true that on a sudden emergency of this character the President would direct any armed force in the vicinity to march to their relief, but in doing this he would act upon his own responsibility.
Under these circumstances I earnestly recommend to Congress the passage of an act authorizing the President, under such restrictions as they may deem proper, to employ the land and naval forces of the United States in preventing the transit from being obstructed or closed by lawless violence, and in protecting the lives and property of American citizens traveling thereupon, requiring at the same time that these forces shall be withdrawn the moment the danger shall have passed away. Without such a provision our citizens will be constantly exposed to interruption in their progress and to lawless violence.
A similar necessity exists for the passage of such an act for the protection of the Panama and Tehuantepec routes.
In reference to the Panama route, the United States, by their existing treaty with New Granada, expressly guarantee the neutrality of the Isthmus, “with the view that the free transit from the one to the other sea may not be interrupted or embarrassed in any future time while this treaty exists.”
In regard to the Tehuantepec route, which has been recently opened under the most favorable auspices, our treaty with Mexico of the 30th December, 1853, secures to the citizens of the United States a right of transit over it for their persons and merchandise and stipulates that neither Government shall “interpose any obstacle” thereto. It also concedes to the United States the “right to transport across the Isthmus, in closed bags, the mails of the United States not intended for distribution along the line of the communication; also the effects of the United States Government and its citizens which may be intended for transit and not for distribution on the Isthmus, free of custom-house or other charges by the Mexican Government.”