Please provide a summary and historical context for the following primary source. The Decision to Act Against Spain William McKinley https://www.tracy.k12.ca.us/sites/rlee/Shared%20Documents/History%20of%20the%20Americas%20II/US%20Latin%20American%20Relations/Sources/McKinley%20Spanish%20American%20War%20Speech.pdf

In the three centuries following Christopher Columbus's discovery of America, Spain had acquired control of vast swathes of territory, from the Caribbean to California and Argentina to the Philippines. By the early nineteenth century, that control was crumbling. The Spanish colonies broke away one by one, and by 1825, Spain's empire was reduced to only a handful of territories—among them, the island of Cuba.
Cuba began to fight for independence from Spain in the 1860s. A decade-long guerrilla war between the Cubans and the Spanish ended in 1878 with an uneasy truce. In 1892, the Cuban Revolutionary Party was founded, and the struggle for independence began anew. In 1895, armed conflict broke out.
The United States was interested in this situation for various reasons:


The US wanted to purchase Cuba from Spain and use the island to grow sugarcane.


Various US companies already owned large tracts of land in Cuba on which they were cultivating sugar. The conflict threatened the crops and consequently the profits of these companies.


Because Cuba was (owned by) a foreign country, the US sugar companies had to pay an import tariff to import their crops into the United States. If the US could purchase Cuba from Spain, Cuba would be a US territory, and the import tariff would no longer apply (meaning higher profits for the companies).


The conflict between Cuba and Spain destabilized the colonial government. The US government could intervene at an opportune moment and either persuade Cuba to join the United States or offer to take the island "off Spain's hands" (so to speak). Either way, the US would acquire Cuba, and the island's lucrative sugar industry.


The "profit-motive" behind US interest in the Cuban-Spanish conflict was insufficient for the US military to intervene, however. In 1895, President Cleveland had declared the US government neutral with regard to the conflict. In 1896, the Spanish governor of Cuba declared martial law on the island, and public sentiment in the United States began to swing in favour of military intervention, as it was now a matter of ethics (the liberation of the oppressed Cubans) rather than purely one of profit.
Into this context, in 1897, William McKinley was inaugurated President of the United States. The Cuban-Spanish conflict continued, and news from the island told horror stories of life under martial law. By 1898, the American public was strongly pressuring Congress to intervene, and when McKinley hesitated, two things happened in swift succession: first, a letter from the Spanish Foreign Minister was published in the New York Journal; it harshly criticized President McKinley and agitated strong anti-Spanish feeling in the United States. Second, the battleship U.S.S. Maine exploded and sank suddenly and mysteriously in Havana Harbour. These events occurred within days of each other. The prevailing theory about the Maine was that the Spanish had bombed it (a theory sensationalised by the national press), and this overtly hostile act was all the justification the US needed not only to intervene in the Cuban situation, but to declare war directly on Spain.
McKinley’s speech is his request to Congress for authorization to declare war. McKinley declares that the current crisis in Cuba is the culmination of decades of Cuban struggle against Spanish rule. He says that the “cruel, barbarous, and uncivilized practices” of the Spanish government have “offended the humane sympathies of our people.” He deplores “that strict neutrality which our laws enjoin,” which has led the United States to stand idle while the Cuban people suffer and their country goes to ruin.
McKinley makes it clear that he does not believe either the Cubans or the Spanish can, on their own, resolve this crisis and that only a war of total attrition could bring the conflict to a close. This is a hideous possibility to contemplate, and the United States has a moral duty to intervene in the conflict to prevent “such a protraction and conclusion of the present strife.”

The forcible intervention of the United States as a neutral to stop the war . . . is justifiable on rational grounds.

McKinley outlines the basis for intervention in four points:


To bring the conflict to a definite conclusion: the Cuban people are suffering horribly under Spanish martial law. They do not have sufficient resources to throw off the Spanish government on their own, and the Spanish do not have the wherewithal to put down the Cuban rebellion once and for all, so the conflict is likely to drag on for years unless some greater power intervenes. That power should be the United States because of its proximity to Cuba and its special interest in the fate of the island. “It is no answer to say this is all in another country, belonging to another nation, and is therefore none of our business. It is specially our duty, for it is right at our door.”


Humane reasons: the people of Cuba are struggling for independence from Spain. At present, they are not citizens of Spain and have no rights or protections from the Spanish crown; they are, in fact, being oppressed by the agents of that crown, and someone should defend them. America is uniquely able to empathize with Cuba’s struggle, having fought for her own independence just over a century before.


Economic reasons: the conflict in Cuba is disrupting all trade in the region and seriously impacting the US economy as a result.


Spain has already declared war on the US: this is evident from the destruction of the U.S.S. Maine, which the Spanish clearly destroyed to “warn” the US from intervening in the conflict. The United States therefore must respond with all appropriate military force.


McKinley concludes his request to Congress by asking that, in light of the facts above, they provide him with authorization to “use the military and naval forces of the United States as may be necessary” to end the conflict in Cuba, drive out the Spanish government there, and establish a stable Cuban government in its place.
The Library of Congress has an excellent overview of the Spanish-American War at this link, if you are interested:
https://www.loc.gov/rr/hispanic/1898/intro.html