The answer for this question is: <span>the election of Abraham Lincoln as President
Abaraham Lincoln was always known as someone that really see slavery as something that undermines human's value.
Not long after elected as president, Abraham Lincoln made several policies that make it harder for the southern states to keep their slaves, which led to the first secession.</span>
"George Washington's proclamation of neutrality was a formal announcement, declaring the nation neutral in the conflict between France and Great Britain."
<span>launched a series of articles in McClure's, called Tweed Days in St. Louis, that would later be published together in a book titled The Shame of the Cities.
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Search-and-destroy missions in Vietnam were largely unsuccessful. This is because new and larger reinforcements of Viet-Kongs moved in as soon as American forces departed. As such, these missions did not stem the flow of refugees.
Definitely the second choice! :)