An expanding America By dirbyhunter21 Apr 25, 1890 Spanish American War Apr 25, 1898 Congress Declares War on Spain Sep 1, 1899 Open Door Policy Jan 1, 1913 Wilson Becomes President Oct 4, 1913 US starts conflict in Panama Period: Apr 6, 1914 to Apr 6, 1917 U.S. Mobilizes for War Aug 15, 1914 Panama Canal Opens Oct 4, 1914 Purto Rico becomes US territory Apr 6, 1917 U.S. Enters WWI Apr 6, 1917 America Sends Troops over Seas for First Time
