There was a time when America desperately needed bird poo. Tropical bird poo, known as guano, to be specific.

Guano -- just like other natural resources such as coal, oil or goldĀ -- played a role in significantly changing U.S. foreign policy.
Guano covers whole islands in the tropical oceans around the world. It is sometimes hundreds of feet thick. There used to be a lot more guano until capitalism woke up one day in the 19th century and realized bird shit smelled like money.
August 18, 1856, 167 years ago, the United States Congress enacted The Guano Islands Act.
The Guano Islands Act is a federal law allowing citizens of the United States to take possession of unclaimed islands containing guano deposits in the name of the United States. And not only that, the islands can be located anywhere.