It also empowers the president to use the military to protect such interests and establishes the criminal jurisdiction of the United States in these territories.

This encouraged American entrepreneurs to search for and exploit new deposits on tiny islands and reefs in the Caribbean and Pacific.

Up until this time, any territory acquired by the U.S. was considered to have become an integral part of the country unless changed by treaty and eventually to have the opportunity to become a state of the Union.

By 1903, 66 of these islands were recognized as territories of the U.S.[5] Whenever any citizen of the United States discovers a deposit of guano on any island, rock, or key, not within the lawful jurisdiction of any other Government, and not occupied by the citizens of any other Government, and takes peaceable possession thereof, and occupies the same, such island, rock, or key may, at the discretion of the president, be considered as appertaining to the United States.Section 6 provides that criminal acts on or adjacent to these territories "shall be deemed committed on the high seas, on board a merchant ship or vessel belonging to the United States; and shall be punished according to the laws of the United States relating to such ships or vessels and offenses on the high seas".

The Act does not specify the territory's status after private U.S. interests abandon it or the guano is exhausted, creating neither obligation nor prohibition of retaining possession.