The question of the Philippines was brought up during the negotiations.
The Americans initially only wanted the naval base in Manila, or at most the island of Luzon, and give the rest back, but seeing the situation that Spain is in they assumed that it is very likely they will sell it to another European power.
This situation, the Americans thought, would likely be troublesome thus they decided to demand the entire archipelago.
The Spanish delegation however was determined to hold on to their country's possession and hoped to only cede the island of Mindanao, or at least the Sulu archipelago.
With the growing risk of the negotiations collapsing, so are the fears of war resuming. In addition, the elections in the US cut the Republican majority in Congress which made the American delegation offer twenty million dollars in exchange for the Philippines.
This, however, did not sit well with the Spanish delegation since this is a tenth of the original estimate, but due Queen-Regent Maria Christina accepting the demand the delegation formally replied that Spain accepts the U.S terms in order to conclude the peace treaty.
During all these negotiations, the Philippines was never consulted on their fate, and the representative they sent, Felipe Agoncillo, was denied participation.
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In the United States Congress after the signing of the treaty, there is a debate on whether or not they should ratify the treaty.
Some just opposed the treaty entirely, some opposed the annexation of the Philippines, while others favored the expansion of U.S territory, and some favored the treaty on the basis of ending the war and granting independence to Cuba and the Philippines.
There are senators who outright spoke against the treaty as this will make America become just another empire that seeks to control and rule over other races. It was also argued to be a violation of the Constitution, as they nor the President do not have the power to pass a law that governs colonial people unrepresented in congress.
Expansionists, however, argued that rejecting the treaty will continue the war and will brand America as incapable of being equal to the other powers of the world. Another stated that it was America's duty to spread Christianity.
Meanwhile, an organization known as the Anti-Imperialist League, whose members also opposed the war with Spain, campaigned against the annexation of the Philippine Islands on various grounds such as moral, economic, legal, and racial.
In the end however, the treaty passed, albeit barely, thus giving the United States ownership of the Philippine Islands.