The latest acquisition of the United States in the Caribbean is that of the Danish West Indies, or Virgin Islands. Reference has already been made to the treaty negotiated by Secretary Seward in 1867 for the purchase of these islands, which was unfortunately rejected by the Senate. Another attempt at purchase was made by President Roosevelt in 1902. A treaty providing for the cession of the group to the United States was signed at Washington on January 24 of that year and approved by the Senate February 17, but this time the Danish Rigsdag refused to give its approval. President Roosevelt was moved by the consideration that the Danish Islands were of great strategic importance in connection with the problem of guarding the approaches to the Panama canal. The commercial value of the islands is also great. Moreover, the United States was confronted by the possibility of their falling under the control of Germany or some other European power, which might use them as a naval base. Had Germany been successful in the recent war, she might have forced Denmark to sell or cede the islands to her. In view of this possibility, negotiations were taken up again with Denmark in 1916, and on August 4 Secretary Lansing concluded a treaty by which the United States acquired the islands of St. Thomas, St. John, and St. Croix, together with some adjacent small islands and rocks, for the sum of $25,000,000. This treaty was duly ratified by the Senate and the ratifications were exchanged January 17, 1917.