The isthmus of Central America, including that of Panama, is the great highway between the Atlantic and Pacific over which a large portion of the commerce of the world is destined to pass. The United States are more deeply interested than any other nation in preserving the freedom and security of all the communications across this isthmus. It is our duty, therefore, to take care that they shall not be interrupted either by invasions from our own country or by wars between the independent States of Central America. Under our treaty with New Granada of the 12th December, 1846, we are bound to guarantee the neutrality of the Isthmus of Panama, through which the Panama Railroad passes, "as well as the rights of sovereignty and property which New Granada has and possesses over the said territory." This obligation is founded upon equivalents granted by the treaty to the Government and people of the United States. Under these circumstances I recommend to Congress the passage of an act authorizing the President, in case of necessity, to employ the land and naval forces of the United States to carry into effect this guaranty of neutrality and protection. I also recommend similar legislation for the security of any other route across the Isthmus in which we may acquire an interest by treaty. With the independent Republics on this continent it is both our duty and our interest to cultivate the most friendly relations. We can never feel indifferent to their fate, and must always rejoice in their prosperity. Unfortunately both for them and for us, our example and advice have lost much of their influence in consequence of the lawless expeditions which have been fitted out against some of them within the limits of our country. Nothing is better calculated to retard our steady material progress or impair our character as a nation than the toleration of such enterprises in violation of the law of nations. It is one of the first and highest duties of any independent state in its relations with the members of the great family of nations to restrain its people from acts of hostile aggression against their citizens or subjects. The most eminent writers on public law do not hesitate to denounce such hostile acts as robbery and murder. Weak and feeble states like those of Central America may not feel themselves able to assert and vindicate their rights. The case would be far different if expeditions were set on foot within our own territories to make private war against a powerful nation. If such expeditions were fitted out from abroad against any portion of our own country, to burn down our cities, murder and plunder our people, and usurp our Government, we should call any power on earth to the strictest account for not preventing such enormities.