Answer:
the answer is the 1861 battle of fort sumter
Explanation:
The smallpox epidemic.
The millitary invasion was devastating but not to the extent of smallpox.
The Jesuits did not really devastate the New World.
Enslavement for sugar plantations mostly occurred with Africans.
Smallpox, brought in by the Columbian Exchange, had a widespread impact that killed a large portion of natives in the Americas.
So the Smallpox epidemic is the answer.
Answer:
that the U.S. and Britain would always be allied