Before Colombia reached the stage, however, where it would agree to enter into negotiations with the United States, it had been reminded by its minister in Washington that it was dangerous not to enter into an agreement. He had declared that if Colombia should refuse to hear the American proposal that a new treaty be entered into, the United States would, in retaliation, denounce the treaty of 1846, and thereafter view with complacency any events which might take place in Panama inimical to Colombia's interests. He had reported further that the United States would, at the first interruption of the railroad service, occupy at once Colombia's territory on the Isthmus and embrace whatever tendency there might be toward separation, in the hope of bringing about the independence of Panama. This, he had concluded, would be a catastrophe of far greater consequence to Colombia than any damage the Republic might suffer by the ratification of a treaty with the United States permitting the building of the canal. His views in the matter were strengthened by a suggestion of Senator Shelby M. Cullom, of Illinois, that if Colombia should continue to refuse to allow the United States to build the canal, which the United States claimed was its right to do under the treaty of 1846, the American Government might invoke a sort of universal right of eminent domain, take the Isthmian territory, and pay Colombia its value in accordance with an appraisement by experts. About this time President Roosevelt wrote a letter to his friend, Dr. Albert D. Shaw, of the Review of Reviews, in which he said that he had been appealed to for aid and encouragement to a revolution at Panama, but that as much as he would like to see such a revolution, he could not lend any encouragement to it. The Republic of Colombia was repeatedly reminded by Secretary Hay that if it did not act promptly the President would take up negotiations with Nicaragua and proceed to construct the canal there. Under these conditions Colombia finally agreed to negotiate the Hay-Herran treaty, which was afterwards rejected by the Colombian Congress. It has been asserted that President Roosevelt took the view all along that under the treaty of 1846, Colombia had no right to prevent the United States from building the canal, and that, in spite of the provision of the Spooner Act requiring him to proceed with the construction of the Nicaragua Canal in the event of the failure of negotiations at Panama, he was determined to exhaust every possible effort before giving up the Panama route. CHAPTER XIX CONTROVERSY WITH COLOMBIA Seldom in the history of international relations has a controversy afforded more grounds for honest difference of opinion than the issue between the United States and Colombia, growing out of the revolution and formation of the new Republic of Panama. The most careful and unprejudiced study still may leave room for doubt as to the real merits of the case.