I've been reading a book on the History of the world.
From here it says the Senate approved a treaty to the building of the Canal. After much lobbying by "Philippe Bunau-Varilla".
The Columbian Senate rejected the treaty because "... it was harmful to the sovereignty of Great Colombia". and "This situation motivated the United States to promote and support the separation of Panama from Colombia."
"Impatient to build the canal, Roosevelt supported Panama’s independence movement." and according to Factbites a Panamanian uprising was engineered by Philippe Bunau-Varilla (a representative of the New Panama Canal Company), other canal supporters, and some local residents.
"On November 3, 1903, the Isthmus of Panama declared its independence. Fifteen days later, the government of the newly established Republic of Panama and the United States signed the Hay-Bunau Varilla treaty which was based on the same conditions that had the previously rejected by Colombia Herrán-Hay treaty."
While the building of the "Panama Canal" is one of the worlds great wonders and a great economic resource, this piece of history is quite telling in how the US thought of Sovereignity.
i.e. The country with the resource rejects the treaty, create a new country with the resource and negotiate with that one.
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